The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti
A file manager or file browser is a computer program that provides a user interface to manage files and folders. The most common operations performed on files or groups of files include creating, renaming, moving or copying and searching for files, as well as modifying file attributes and file permissions. Folders and files may be displayed in a hierarchical tree based on their directory structure; some file managers contain features inspired by web browsers, including forward and back navigational buttons. Some file managers provide network connectivity via protocols, such as FTP, HTTP, NFS, SMB or WebDAV; this is achieved by allowing the user to browse for a file server or by providing its own full client implementations for file server protocols. A term that predates the usage of file manager is directory editor. An early directory editor, DIRED, was developed circa 1974 at the Stanford Artificial Intelligence Laboratory by Stan Kugell. A directory editor was written for EXEC 8 at the University of Maryland, was available to other users at that time.
The term was used by other developers, including Jay Lepreau, who wrote the dired program in 1980, which ran on BSD. This was in turn inspired by an older program with the same name running on TOPS-20. Dired inspired other programs, including dired, the editor script, ded. File-list file managers are older than orthodox file managers. One such file manager is flist, introduced sometime before 1980 on the Conversational Monitor System; this is a variant of fulist, which originated before late 1978, according to comments by its author, Theo Alkema. The flist program provided a list of files in the user's minidisk, allowed sorting by any file attribute; the file attributes could be passed to scripts or function-key definitions, making it simple to use flist as part of CMS EXEC, EXEC 2 or XEDIT scripts. This program ran only on IBM VM/SP CMS, but was the inspiration for other programs, including filelist, programs running on other operating systems, including a program called flist, which ran on OpenVMS, fulist, which runs on Unix.
Orthodox file managers or command-based file managers are text-menu based file managers, that have three windows. Orthodox file managers are one of the longest running families of file managers, preceding graphical user interface-based types. Developers create applications that duplicate and extend the manager, introduced by PathMinder and John Socha's famous Norton Commander for DOS; the concept dates to the mid-1980s—PathMinder was released in 1984, Norton Commander version 1.0 was released in 1986. Despite the age of this concept, file managers based on Norton Commander are developed, dozens of implementations exist for DOS, Microsoft Windows. Nikolai Bezroukov publishes his own set of criteria for an OFM standard. An orthodox file manager has three windows. Two of the windows are positioned symmetrically at the top of the screen; the third is the command line, a minimized command window that can be expanded to full screen. Only one of the panels is active at a given time; the active panel contains the "file cursor".
Panels can be hidden. Files in the active panel serve. For example, files can be copied or moved from the active panel to the location represented in the passive panel; this scheme is most effective for systems in which the keyboard is the sole input device. The active panel shows information about the current working directory and the files that it contains; the passive panel shows the content of another directory. Users may customize the display of columns; the active panel and passive panel can be switched. The following features describe the class of orthodox file managers, they present the user with a two-panel directory view with a command line below. Either panel may be selected to be active; the active panel becomes the working area for delete and rename operations, while the passive panel serves as a target for copy and move operations. Panels may be shrunk. Only the last line of the terminal window is visible, they provide close integration with an underlying OS shell via command line, using the associated terminal window that permits viewing the results of executing shell commands entered on the command line.
They provide the user with extensive keyboard shortcuts. The file manager frees the user from having to use the mouse. Users can create their own file associations and scripts that are invoked for certain file types and organize these scripts into a hierarchical tree. Users can extend the functionality of the manager via a so-called User menu or Start menu and extensions menu. Other common features include: Information on the "active" and "passive" panels may be used for constructing commands on the command line. Examples include path to left panel, path to right panel, etc.. They provide a built-in viewer for the most basic file types, they have a built-in editor. In many cases, the editor can extract certain elements o
Microsoft Windows is a group of several graphical operating system families, all of which are developed and sold by Microsoft. Each family caters to a certain sector of the computing industry. Active Windows families include Windows Embedded. Defunct Windows families include Windows Mobile and Windows Phone. Microsoft introduced an operating environment named Windows on November 20, 1985, as a graphical operating system shell for MS-DOS in response to the growing interest in graphical user interfaces. Microsoft Windows came to dominate the world's personal computer market with over 90% market share, overtaking Mac OS, introduced in 1984. Apple came to see Windows as an unfair encroachment on their innovation in GUI development as implemented on products such as the Lisa and Macintosh. On PCs, Windows is still the most popular operating system. However, in 2014, Microsoft admitted losing the majority of the overall operating system market to Android, because of the massive growth in sales of Android smartphones.
In 2014, the number of Windows devices sold was less than 25 %. This comparison however may not be relevant, as the two operating systems traditionally target different platforms. Still, numbers for server use of Windows show one third market share, similar to that for end user use; as of October 2018, the most recent version of Windows for PCs, tablets and embedded devices is Windows 10. The most recent versions for server computers is Windows Server 2019. A specialized version of Windows runs on the Xbox One video game console. Microsoft, the developer of Windows, has registered several trademarks, each of which denote a family of Windows operating systems that target a specific sector of the computing industry; as of 2014, the following Windows families are being developed: Windows NT: Started as a family of operating systems with Windows NT 3.1, an operating system for server computers and workstations. It now consists of three operating system subfamilies that are released at the same time and share the same kernel: Windows: The operating system for mainstream personal computers and smartphones.
The latest version is Windows 10. The main competitor of this family is macOS by Apple for personal computers and Android for mobile devices. Windows Server: The operating system for server computers; the latest version is Windows Server 2019. Unlike its client sibling, it has adopted a strong naming scheme; the main competitor of this family is Linux. Windows PE: A lightweight version of its Windows sibling, meant to operate as a live operating system, used for installing Windows on bare-metal computers, recovery or troubleshooting purposes; the latest version is Windows PE 10. Windows IoT: Initially, Microsoft developed Windows CE as a general-purpose operating system for every device, too resource-limited to be called a full-fledged computer. However, Windows CE was renamed Windows Embedded Compact and was folded under Windows Compact trademark which consists of Windows Embedded Industry, Windows Embedded Professional, Windows Embedded Standard, Windows Embedded Handheld and Windows Embedded Automotive.
The following Windows families are no longer being developed: Windows 9x: An operating system that targeted consumers market. Discontinued because of suboptimal performance. Microsoft now caters to the consumer market with Windows NT. Windows Mobile: The predecessor to Windows Phone, it was a mobile phone operating system; the first version was called Pocket PC 2000. The last version is Windows Mobile 6.5. Windows Phone: An operating system sold only to manufacturers of smartphones; the first version was Windows Phone 7, followed by Windows Phone 8, the last version Windows Phone 8.1. It was succeeded by Windows 10 Mobile; the term Windows collectively describes any or all of several generations of Microsoft operating system products. These products are categorized as follows: The history of Windows dates back to 1981, when Microsoft started work on a program called "Interface Manager", it was announced in November 1983 under the name "Windows", but Windows 1.0 was not released until November 1985.
Windows 1.0 was to achieved little popularity. Windows 1.0 is not a complete operating system. The shell of Windows 1.0 is a program known as the MS-DOS Executive. Components included Calculator, Cardfile, Clipboard viewer, Control Panel, Paint, Reversi and Write. Windows 1.0 does not allow overlapping windows. Instead all windows are tiled. Only modal dialog boxes may appear over other windows. Microsoft sold as included Windows Development libraries with the C development environment, which included numerous windows samples. Windows 2.0 was released in December 1987, was more popular than its predecessor. It features several improvements to the user memory management. Windows 2.03 changed the OS from tiled windows to overlapping windows. The result of this change led to Apple Computer filing a suit against Microsoft alleging infringement on Apple's copyrights. Windows 2.0