Arrow keys or cursor movement keys are buttons on a computer keyboard that are either programmed or designated to move the cursor in a specified direction. The term "cursor movement key" is distinct from "arrow key" in that the former term may refer to any of various keys on a computer keyboard designated for cursor movement, whereas "arrow keys" refers to one of four specific keys marked with arrows. Arrow keys are located at the bottom of the keyboard to the left side of the numeric keypad arranged in an inverted-T layout but found in diamond shapes and linear shapes. Arrow keys are used for navigating around documents and for playing games; the inverted-T layout was popularized by the Digital Equipment Corporation LK201 keyboard from 1982. Before the computer mouse was widespread, arrow keys were the primary way of moving a cursor on screen. Mouse keys is a feature. A feature echoed in the Amiga whereby holding the Amiga key would allow a person to move the pointer with the arrow keys in the Workbench, but most games require a mouse or joystick.
The use of arrow keys in games has come back into fashion from the late 1980s and early 1990s when joysticks were a must, were used in preference to arrow keys with some games not supporting any keys. It can be used instead of WASD keys; the inverted-T layout was popularized by the Digital Equipment Corporation LK201 keyboard from 1982. Some Commodore 8-bit computers used two keys instead of four, with directions selected using the shift key; the original Apple Macintosh had no arrow keys at the insistence of Steve Jobs, who felt that people should use the mouse instead. They were deliberately excluded from the Macintosh launch design as a forcing device, acclimating users to the new mouse input device and inducing software developers to conform to mouse-driven design rather than porting previous terminal-based software to the new platform. Arrow keys were included in Apple keyboards. Early models with arrow keys but no middle section placed them in one line below the right-hand Shift key in an HJKL-like fashion.
Although the "arrow keys" provide one convention for cursor movement on computers, there are other conventions for cursor movement that use different keys. This layout dates back to Sinclair ZX80, Sinclair ZX81, Sinclair Spectrum software: the original Sinclair machines had cursor keys on the top row, keys 5, 6, 7, 8. Due to the unusual layout adopted by Sinclair, these keys were accessed either by using the ⇧ Shift key in conjunction with a numeric key or by the numeric key alone, depending on the program in use. WASD is a set of four keys on a QWERTY or QWERTZ computer keyboard which mimics the inverted-T configuration of the arrow keys; these keys are used to control the player character's movement in computer games, most first person games but in many driving and third person games. W/S control forward and backward, while A/D control strafing left and right. WASD is used to account for the fact that the arrow keys are not ergonomic to use in conjunction with a right-handed mouse. During the early days of gaming, this was not a problem.
However, the introduction of mouselook, a system that allowed the ability to use the mouse to look around both vertically and horizontally, enabled the player to perform techniques such as smooth circle strafing, although possible with the keyboard, was difficult to perform and resulted in jagged movement. Since the mouse was now used for looking, the ← and → keys for looking would be redundant and thus were altered to become strafe keys; the style was popularized in competitive play in Quake and subsequently QuakeWorld, notably by professional gamer Dennis Fong, where the advantages of WASD and mouselook were recognised over a purely keyboard-based control system. In the same year that Castle Wolfenstein was released, 1981, the game Wizardry used the AWD keys for movement in a 3D dungeon. Both the programmers of Castle Wolfenstein and Wizardry were users of the earlier PLATO system where the game Moria used the AWD keys. Another advantage of WASD is that it allows the user to use the left hand thumb to press the space bar and the left hand little finger to press the Ctrl or ⇧ Shift keys, as opposed to the arrow keys which lack other keys in proximity to press.
Ctrl and ⇧ Shift were chosen because they are larger keys and thus easier to hit, but because in older systems the computer could only recognise a couple of alphanumeric key presses, a limitation circumvented by the use of modifier keys. In games, the usage of the E key to interact with items or open up the inventory was popularized due to its location next to the WASD keys, allowing players to reach it quickly. Dark Castle may be the first game to use WASD keys and mouse for control. Half-Life was one of the first games to use WASD by default. After being popularized by first-person shooters, WASD became more common in other computer game genres as well. Many of the games that have adopted this layout use a first-person or over-the-shoulder third-person perspective; some games that use overhead camera views use WASD to move the camera, such as some city-building games and economic simulation games. Th
Central processing unit
A central processing unit called a central processor or main processor, is the electronic circuitry within a computer that carries out the instructions of a computer program by performing the basic arithmetic, logic and input/output operations specified by the instructions. The computer industry has used the term "central processing unit" at least since the early 1960s. Traditionally, the term "CPU" refers to a processor, more to its processing unit and control unit, distinguishing these core elements of a computer from external components such as main memory and I/O circuitry; the form and implementation of CPUs have changed over the course of their history, but their fundamental operation remains unchanged. Principal components of a CPU include the arithmetic logic unit that performs arithmetic and logic operations, processor registers that supply operands to the ALU and store the results of ALU operations and a control unit that orchestrates the fetching and execution of instructions by directing the coordinated operations of the ALU, registers and other components.
Most modern CPUs are microprocessors, meaning they are contained on a single integrated circuit chip. An IC that contains a CPU may contain memory, peripheral interfaces, other components of a computer; some computers employ a multi-core processor, a single chip containing two or more CPUs called "cores". Array processors or vector processors have multiple processors that operate in parallel, with no unit considered central. There exists the concept of virtual CPUs which are an abstraction of dynamical aggregated computational resources. Early computers such as the ENIAC had to be physically rewired to perform different tasks, which caused these machines to be called "fixed-program computers". Since the term "CPU" is defined as a device for software execution, the earliest devices that could rightly be called CPUs came with the advent of the stored-program computer; the idea of a stored-program computer had been present in the design of J. Presper Eckert and John William Mauchly's ENIAC, but was omitted so that it could be finished sooner.
On June 30, 1945, before ENIAC was made, mathematician John von Neumann distributed the paper entitled First Draft of a Report on the EDVAC. It was the outline of a stored-program computer that would be completed in August 1949. EDVAC was designed to perform a certain number of instructions of various types; the programs written for EDVAC were to be stored in high-speed computer memory rather than specified by the physical wiring of the computer. This overcame a severe limitation of ENIAC, the considerable time and effort required to reconfigure the computer to perform a new task. With von Neumann's design, the program that EDVAC ran could be changed by changing the contents of the memory. EDVAC, was not the first stored-program computer. Early CPUs were custom designs used as part of a sometimes distinctive computer. However, this method of designing custom CPUs for a particular application has given way to the development of multi-purpose processors produced in large quantities; this standardization began in the era of discrete transistor mainframes and minicomputers and has accelerated with the popularization of the integrated circuit.
The IC has allowed complex CPUs to be designed and manufactured to tolerances on the order of nanometers. Both the miniaturization and standardization of CPUs have increased the presence of digital devices in modern life far beyond the limited application of dedicated computing machines. Modern microprocessors appear in electronic devices ranging from automobiles to cellphones, sometimes in toys. While von Neumann is most credited with the design of the stored-program computer because of his design of EDVAC, the design became known as the von Neumann architecture, others before him, such as Konrad Zuse, had suggested and implemented similar ideas; the so-called Harvard architecture of the Harvard Mark I, completed before EDVAC used a stored-program design using punched paper tape rather than electronic memory. The key difference between the von Neumann and Harvard architectures is that the latter separates the storage and treatment of CPU instructions and data, while the former uses the same memory space for both.
Most modern CPUs are von Neumann in design, but CPUs with the Harvard architecture are seen as well in embedded applications. Relays and vacuum tubes were used as switching elements; the overall speed of a system is dependent on the speed of the switches. Tube computers like EDVAC tended to average eight hours between failures, whereas relay computers like the Harvard Mark I failed rarely. In the end, tube-based CPUs became dominant because the significant speed advantages afforded outweighed the reliability problems. Most of these early synchronous CPUs ran at low clock rates compared to modern microelectronic designs. Clock signal frequencies ranging from 100 kHz to 4 MHz were common at this time, limited by the speed of the switching de
An operating system is system software that manages computer hardware and software resources and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may include accounting software for cost allocation of processor time, mass storage and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is executed directly by the hardware and makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer – from cellular phones and video game consoles to web servers and supercomputers; the dominant desktop operating system is Microsoft Windows with a market share of around 82.74%. MacOS by Apple Inc. is in second place, the varieties of Linux are collectively in third place. In the mobile sector, use in 2017 is up to 70% of Google's Android and according to third quarter 2016 data, Android on smartphones is dominant with 87.5 percent and a growth rate 10.3 percent per year, followed by Apple's iOS with 12.1 percent and a per year decrease in market share of 5.2 percent, while other operating systems amount to just 0.3 percent.
Linux distributions are dominant in supercomputing sectors. Other specialized classes of operating systems, such as embedded and real-time systems, exist for many applications. A single-tasking system can only run one program at a time, while a multi-tasking operating system allows more than one program to be running in concurrency; this is achieved by time-sharing, where the available processor time is divided between multiple processes. These processes are each interrupted in time slices by a task-scheduling subsystem of the operating system. Multi-tasking may be characterized in co-operative types. In preemptive multitasking, the operating system slices the CPU time and dedicates a slot to each of the programs. Unix-like operating systems, such as Solaris and Linux—as well as non-Unix-like, such as AmigaOS—support preemptive multitasking. Cooperative multitasking is achieved by relying on each process to provide time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking.
32-bit versions of both Windows NT and Win9x, used preemptive multi-tasking. Single-user operating systems have no facilities to distinguish users, but may allow multiple programs to run in tandem. A multi-user operating system extends the basic concept of multi-tasking with facilities that identify processes and resources, such as disk space, belonging to multiple users, the system permits multiple users to interact with the system at the same time. Time-sharing operating systems schedule tasks for efficient use of the system and may include accounting software for cost allocation of processor time, mass storage and other resources to multiple users. A distributed operating system manages a group of distinct computers and makes them appear to be a single computer; the development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine; when computers in a group work in cooperation, they form a distributed system.
In an OS, distributed and cloud computing context, templating refers to creating a single virtual machine image as a guest operating system saving it as a tool for multiple running virtual machines. The technique is used both in virtualization and cloud computing management, is common in large server warehouses. Embedded operating systems are designed to be used in embedded computer systems, they are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources, they are compact and efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems. A real-time operating system is an operating system that guarantees to process events or data by a specific moment in time. A real-time operating system may be single- or multi-tasking, but when multitasking, it uses specialized scheduling algorithms so that a deterministic nature of behavior is achieved. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.
A library operating system is one in which the services that a typical operating system provides, such as networking, are provided in the form of libraries and composed with the application and configuration code to construct a unikernel: a specialized, single address space, machine image that can be deployed to cloud or embedded environments. Early computers were built to perform a series of single tasks, like a calculator. Basic operating system features were developed in the 1950s, such as resident monitor functions that could automatically run different programs in succession to speed up processing. Operating systems did not exist in their more complex forms until the early 1960s. Hardware features were added, that enabled use of runtime libraries and parallel processing; when personal computers became popular in the 1980s, operating systems were made for them similar in concept to those used on larger computers. In the 1940s, the earliest electronic digital systems had no operating systems.
Electronic systems of this time were programmed on rows of mechanical switches or by jumper wires on plug boards. These were special-purpose systems that, for example, generated ballistics tables for the military or controlled the pri
The Motorola 68000 is a 16/32-bit CISC microprocessor, which implements a 32-bit instruction set, with 32-bit registers and 32-bit internal data bus, but with a 16-bit data ALU and two 16-bit arithmetic ALUs and a 16-bit external data bus and marketed by Motorola Semiconductor Products Sector. Introduced in 1979 with HMOS technology as the first member of the successful 32-bit Motorola 68000 series, it is software forward-compatible with the rest of the line despite being limited to a 16-bit wide external bus. After 39 years in production, the 68000 architecture is still in use; the 68000 grew out of the MACSS project, begun in 1976 to develop an new architecture without backward compatibility. It would be a higher-power sibling complementing the existing 8-bit 6800 line rather than a compatible successor. In the end, the 68000 did retain a bus protocol compatibility mode for existing 6800 peripheral devices, a version with an 8-bit data bus was produced. However, the designers focused on the future, or forward compatibility, which gave the 68000 design a head start against 32-bit instruction set architectures.
For instance, the CPU registers are 32 bits wide, though few self-contained structures in the processor itself operate on 32 bits at a time. The MACSS team drew on the influence of minicomputer processor design, such as the PDP-11 and VAX systems, which were microcode-based. In the mid 1970s, the 8-bit microprocessor manufacturers raced to introduce the 16-bit generation. National Semiconductor had been first with its IMP-16 and PACE processors in 1973–1975, but these had issues with speed. Intel had worked on their advanced 16/32-bit Intel iAPX 432 since 1975 and their Intel 8086 since 1976. Arriving late to the 16-bit arena afforded the new processor more transistors, 32-bit macroinstructions, acclaimed general ease of use; the original MC68000 was fabricated using an HMOS process with a 3.5 µm feature size. Formally introduced in September 1979, initial samples were released in February 1980, with production chips available over the counter in November. Initial speed grades were 4, 6, 8 MHz. 10 MHz chips became available during 1981, 12.5 MHz chips by June 1982.
The 16.67 MHz "12F" version of the MC68000, the fastest version of the original HMOS chip, was not produced until the late 1980s. The 68k instruction set was well suited to implement Unix, the 68000 and its successors became the dominant CPUs for Unix-based workstations including Sun workstations and Apollo/Domain workstations; the 68000 was used for mass-market computers such as the Apple Lisa, Macintosh and Atari ST. The 68000 was used in Microsoft Xenix systems, as well as an early NetWare Unix-based Server; the 68000 was used in the first generation of desktop laser printers, including the original Apple Inc. LaserWriter and the HP LaserJet. In 1982, the 68000 received an update to its ISA allowing it to support virtual memory and to conform to the Popek and Goldberg virtualization requirements; the updated chip was called the 68010. A further extended version, which exposed 31 bits of the address bus, was produced in small quantities as the 68012. To support lower-cost systems and control applications with smaller memory sizes, Motorola introduced the 8-bit compatible MC68008 in 1982.
This was a 68000 with a smaller address bus. After 1982, Motorola devoted more attention to the 88000 projects. Several other companies were second-source manufacturers of the HMOS 68000; these included Hitachi, who shrank the feature size to 2.7 µm for their 12.5 MHz version, Rockwell, Thomson/SGS-Thomson, Toshiba. Toshiba was a second-source maker of the CMOS 68HC000. Encrypted variants of the 68000, being the Hitachi FD1089 and FD1094, store decryption keys for opcodes and opcode data in battery-backed memory and were used in certain Sega arcade systems including System 16 to prevent piracy and illegal bootleg games; the 68HC000, the first CMOS version of the 68000, was designed by Hitachi and jointly introduced in 1985. Motorola's version was called the MC68HC000, while Hitachi's was the HD68HC000; the 68HC000 was offered at speeds of 8–20 MHz. Except for using CMOS circuitry, it behaved identically to the HMOS MC68000, but the change to CMOS reduced its power consumption; the original HMOS MC68000 consumed around 1.35 watts at an ambient temperature of 25 °C, regardless of clock speed, while the MC68HC000 consumed only 0.13 watts at 8 MHz and 0.38 watts at 20 MHz.
Apple selected the 68HC000 for use in the Macintosh Portable. Motorola replaced the MC68008 with the MC68HC001 in 1990; this chip resembled the 68HC000 in most respects, but its data bus could operate in either 16-bit or 8-bit mode, depending on the value of an input pin at reset. Thus, like the 68008, it could be used in systems with cheaper 8-bit memories; the evolution of the 68000 focused on more modern embedded control applications and on-chip peripherals. The 68EC000 chip and SCM68000 core expanded the address bus to 32 bits, removed the M6800 peripheral bus, excluded the MOVE from SR instruction from user mode programs. In 1996, Motorola updated the standalone core with static circuitry, drawing only 2 µW in l
Fortran is a general-purpose, compiled imperative programming language, suited to numeric computation and scientific computing. Developed by IBM in the 1950s for scientific and engineering applications, FORTRAN came to dominate this area of programming early on and has been in continuous use for over half a century in computationally intensive areas such as numerical weather prediction, finite element analysis, computational fluid dynamics, computational physics and computational chemistry, it is a popular language for high-performance computing and is used for programs that benchmark and rank the world's fastest supercomputers. Fortran encompasses a lineage of versions, each of which evolved to add extensions to the language while retaining compatibility with prior versions. Successive versions have added support for structured programming and processing of character-based data, array programming, modular programming and generic programming, high performance Fortran, object-oriented programming and concurrent programming.
Fortran's design was the basis for many other programming languages. Among the better known is BASIC, based on FORTRAN II with a number of syntax cleanups, notably better logical structures, other changes to more work in an interactive environment; the names of earlier versions of the language through FORTRAN 77 were conventionally spelled in all-capitals. The capitalization has been dropped in referring to newer versions beginning with Fortran 90; the official language standards now refer to the language as "Fortran" rather than all-caps "FORTRAN". In late 1953, John W. Backus submitted a proposal to his superiors at IBM to develop a more practical alternative to assembly language for programming their IBM 704 mainframe computer. Backus' historic FORTRAN team consisted of programmers Richard Goldberg, Sheldon F. Best, Harlan Herrick, Peter Sheridan, Roy Nutt, Robert Nelson, Irving Ziller, Lois Haibt, David Sayre, its concepts included easier entry of equations into a computer, an idea developed by J. Halcombe Laning and demonstrated in the Laning and Zierler system of 1952.
A draft specification for The IBM Mathematical Formula Translating System was completed by November 1954. The first manual for FORTRAN appeared in October 1956, with the first FORTRAN compiler delivered in April 1957; this was the first optimizing compiler, because customers were reluctant to use a high-level programming language unless its compiler could generate code with performance comparable to that of hand-coded assembly language. While the community was skeptical that this new method could outperform hand-coding, it reduced the number of programming statements necessary to operate a machine by a factor of 20, gained acceptance. John Backus said during a 1979 interview with Think, the IBM employee magazine, "Much of my work has come from being lazy. I didn't like writing programs, so, when I was working on the IBM 701, writing programs for computing missile trajectories, I started work on a programming system to make it easier to write programs."The language was adopted by scientists for writing numerically intensive programs, which encouraged compiler writers to produce compilers that could generate faster and more efficient code.
The inclusion of a complex number data type in the language made Fortran suited to technical applications such as electrical engineering. By 1960, versions of FORTRAN were available for the IBM 709, 650, 1620, 7090 computers; the increasing popularity of FORTRAN spurred competing computer manufacturers to provide FORTRAN compilers for their machines, so that by 1963 over 40 FORTRAN compilers existed. For these reasons, FORTRAN is considered to be the first used programming language supported across a variety of computer architectures; the development of Fortran paralleled the early evolution of compiler technology, many advances in the theory and design of compilers were motivated by the need to generate efficient code for Fortran programs. The initial release of FORTRAN for the IBM 704 contained 32 statements, including: DIMENSION and EQUIVALENCE statements Assignment statements Three-way arithmetic IF statement, which passed control to one of three locations in the program depending on whether the result of the arithmetic statement was negative, zero, or positive IF statements for checking exceptions.
The arithmetic IF statement was reminiscent of a three-way comparison instruction available on the 704. The statement provided the only way to compare numbers – by testing their difference, with an attendant risk of overflow; this deficiency was overcome by "logical" facilities introduced in FORTRAN IV. The FREQUENCY statement was used to give branch probabilities for the three branch cases of the arithmetic IF statement; the first FORTRAN compiler used this weighting to perform at compile time a Monte Carlo simulation of the generated code, the results of which were used to optimize the
Prettyprint is the application of any of various stylistic formatting conventions to text files, such as source code and similar kinds of content. These formatting conventions can adjust positioning and spacing, add color and contrast, adjust size, make similar modifications intended to make the content easier for people to view and understand. Prettyprinters for programming language source code are sometimes called code beautifier. Pretty-printing refers to displaying mathematical expressions similar to the way they would be typeset professionally. For example, in computer algebra systems such as Maxima or Mathematica the system may write output like "x ^ 2 + 3 * x" as " x 2 + 3 x "; some graphing calculators, such as the Casio 9860 series, HP-49 series, TI-84 Plus, TI-89, TI-Nspire, the TI-83 Plus with the PrettyPt add-on, or the TI-84 Plus with the same add-on or the "MathPrint"-enabled OSes, can perform pretty-printing. Additionally, a number of newer scientific calculators are equipped with dot matrix screens capable of pretty-printing such as the Casio FX-ES series, Sharp EL-W series, HP SmartCalc 300s, TI-30XB.
Many text formatting programs can typeset mathematics: TeX was developed for high-quality mathematical typesetting. Pretty-printing in markup language instances is most associated with indentation of tags and string content to visually determine hierarchy and nesting. Although the syntactical structures of tag-based languages do not vary, the indentation may vary due to how a markup language is interpreted or due to the data it describes. In MathML, whitespace characters do not reflect data, meaning, or syntax above what is required by XML syntax. In HTML, whitespace characters between tags are considered text and are parsed as text nodes into the parsed result. While indentation may be generously applied to a MathML document, sufficient additional care must be taken in prettyprinting an HTML document to ensure additional text nodes are not created or destroyed in general proximity to the content or content-reflective tag elements; this difference in complexity is non-trivial from the perspective of an automated pretty-print operation where no special rules or edge cases are necessary, as in the more simple MathML example.
The HTML example may require a series of progressive interrelated algorithms to account for various patterns of tag elements and content that conforms to a uniform style and is consistent in application across various instances, as evidenced by the markup.ts application component used to beautify HTML, XML, related technologies for the Pretty Diff tool. Programmers use tools to format programming language source code in a particular manner. Proper code formatting makes it easier to understand. Different programmers prefer different styles of formatting, such as the use of code indentation and whitespace or positioning of braces. A code formatter converts source code from one format style to another; this is straightforward because of the unambiguous syntax of programming languages. Code beautification involves parsing the source code into component structures, such as assignment statements, if blocks, etc. and formatting them in a manner specified by the user in a configuration file. Code beautifiers exist as standalone applications and built into text editors and integrated development environments.
For example, Emacs' various language modes can indent blocks of code attractively. An early example of pretty-printing was Bill Gosper's "GRINDEF" program, which used combinatorial search with pruning to format LISP programs. Early versions operated on the executable form of the Lisp program and were oblivious to the special meanings of various functions. Versions had special read conventions for incorporating non-executable comments and for preserving read macros in unexpanded form, they allowed special indentation conventions for special functions such as if. The term "grind" was used in some Lisp circles as a synonym for pretty-printing. Many open source projects have established rules for code layout; the most typical are the BSD style. The biggest difference between the two is the location of the braces: in the GNU style and closing braces are on lines by themselves, with the same indent. BSD style places an opening brace at the end of the preceding line, the closing braces can be followed by else.
The size of indent and location of whitespace differs. The following example shows some typical C structures and how various indentation style rules format them. Without any formatting at all, it looks like this: The GNU indent program produces the following output when asked to indent according to the GNU rules: It produces this output when formatting according to BSD rules: Formatted text can be considered a generalized form of pretty-printing. Elastic tabstop, a feature of some source code editors that detects and maintains aligned indents enscript, a general text printing tool with prettyprinting functions indent Pretty Diff a pretty printer attached to a file comparison tool, such as a diff utility Algorithm 268: ALGOL 60 reference language editor William M. McKeeman: Commun. ACM 8: 667-668 lgrind, Comprehensive TEX Archive Network NEATER2: a PL/I source statement reformatter Kenneth Conrow, Ronald G. Smith: Commun. ACM 13: 669-675 SOAP - A Program which Documents and Edits ALGOL 60 Programs.
R. S. Scowen, D. Allin, A. L. Hillman, M. Shimell: Comput. J. 14: 133-135 Original SOAP Source Code from
Motorola, Inc. was an American multinational telecommunications company founded on September 25, 1928, based in Schaumburg, Illinois. After having lost $4.3 billion from 2007 to 2009, the company was divided into two independent public companies, Motorola Mobility and Motorola Solutions on January 4, 2011. Motorola Solutions is considered to be the direct successor to Motorola, as the reorganization was structured with Motorola Mobility being spun off. Motorola Mobility was sold to Google in 2012, acquired by Lenovo in 2014. Motorola designed and sold wireless network equipment such as cellular transmission base stations and signal amplifiers. Motorola's home and broadcast network products included set-top boxes, digital video recorders, network equipment used to enable video broadcasting, computer telephony, high-definition television, its business and government customers consisted of wireless voice and broadband systems, public safety communications systems like Astro and Dimetra. These businesses are now part of Motorola Solutions.
Google sold Motorola Home to the Arris Group in December 2012 for US$2.35 billion. Motorola's wireless telephone handset division was a pioneer in cellular telephones. Known as the Personal Communication Sector prior to 2004, it pioneered the "mobile phone" with DynaTAC, "flip phone" with the MicroTAC, as well as the "clam phone" with the StarTAC in the mid-1990s, it had staged a resurgence by the mid-2000s with the Razr, but lost market share in the second half of that decade. It focused on smartphones using Google's open-source Android mobile operating system; the first phone to use the newest version of Google's open source OS, Android 2.0, was released on November 2, 2009 as the Motorola Droid. The handset division was spun off into the independent Motorola Mobility. On May 22, 2012, Google CEO Larry Page announced that Google had closed on its deal to acquire Motorola Mobility. On January 29, 2014, Page announced that, pending closure of the deal, Motorola Mobility would be acquired by Chinese technology company Lenovo for US$2.91 billion.
On October 30, 2014, Lenovo finalized its purchase of Motorola Mobility from Google. Motorola started in Chicago, Illinois, as Galvin Manufacturing Corporation in 1928 when brothers Paul V. and Joseph E. Galvin purchased the bankrupt Stewart Battery Company's battery-eliminator plans and manufacturing equipment at auction for $750. Galvin Manufacturing Corporation set up shop in a small section of a rented building; the company had $565 in five employees. The first week's payroll was $63; the company's first products were the battery eliminators, devices that enabled battery-powered radios to operate on household electricity. Due to advances in radio technology, battery-eliminators soon became obsolete. Paul Galvin learned that some radio technicians were installing sets in cars, challenged his engineers to design an inexpensive car radio that could be installed in most vehicles, his team was successful, Galvin was able to demonstrate a working model of the radio at the June 1930 Radio Manufacturers Association convention in Atlantic City, New Jersey.
He brought home enough orders to keep the company in business. Paul Galvin wanted a brand name for Galvin Manufacturing Corporation's new car radio, created the name “Motorola” by linking "motor" with "ola", a popular ending for many companies at the time, e.g. Moviola, Crayola; the company sold its first Motorola branded radio on June 23, 1930, to Herbert C. Wall of Fort Wayne, for $30. Wall went on to become one of the first Motorola distributors in the country; the Motorola brand name became so well known that Galvin Manufacturing Corporation changed its name to Motorola, Inc. Galvin Manufacturing Corporation began selling Motorola car-radio receivers to police departments and municipalities in November 1930; the company's first public safety customers included the Village of River Forest, Village of Bellwood Police Department, City of Evanston Police, Illinois State Highway Police, Cook County Police with a one-way radio communication. In the same year, the company built its research and development program with Dan Noble, a pioneer in FM radio and semiconductor technologies, who joined the company as director of research.
The company produced the hand-held AM SCR-536 radio during World War II, vital to Allied communication. Motorola ranked 94th among United States corporations in the value of World War II military production contracts. Motorola went public in 1943, became Motorola, Inc. in 1947. At that time Motorola's main business was selling televisions and radios. In October 1946 Motorola communications equipment carried the first calls on Illinois Bell telephone company's new car radiotelephone service in Chicago; the company began making televisions in 1947, with the model VT-71 with 7-inch cathode ray tube. In 1952, Motorola opened its first international subsidiary in Toronto, Canada to produce radios and televisions. In 1953, the company established the Motorola Foundation to support leading universities in the United States. In 1955, years after Motorola started its research and development laboratory in Phoenix, Arizona, to research new solid-state technology, Motorola introduced the world's first commercial high-power germanium-based transistor.