The island of Delos, near Mykonos, near the centre of the Cyclades archipelago, is one of the most important mythological and archaeological sites in Greece. The excavations in the island are among the most extensive in the Mediterranean. Delos had a position as a holy sanctuary for a millennium before Olympian Greek mythology made it the birthplace of Apollo and Artemis. From its Sacred Harbour, the horizon shows the three conical mounds that have identified landscapes sacred to a goddess in other sites: one, retaining its Pre-Greek name Mount Kynthos, is crowned with a sanctuary of Zeus. Established as a cult center, Delos had an importance that its natural resources could never have offered. In this vein Leto, searching for a birthing-place for Artemis and Apollo, addressed the island: Delos, if you would be willing to be the abode of my son Phoebus Apollo and make him a rich temple –, but if you have the temple of far-shooting Apollo, all men will bring you hecatombs and gather here, incessant savour of rich sacrifice will always arise, you will feed those who dwell in you from the hand of strangers.

Investigation of ancient stone huts found on the island indicate that it has been inhabited since the 3rd millennium BC. Thucydides identifies the original inhabitants as piratical Carians who were expelled by King Minos of Crete. By the time of the Odyssey the island was famous as the birthplace of the twin gods Apollo and Artemis. Indeed, between 900 BC and 100 AD, sacred Delos was a major cult centre, where Dionysus is in evidence as well as the Titaness Leto, mother of the above-mentioned twin deities. Acquiring Panhellenic religious significance, Delos was a religious pilgrimage for the Ionians. A number of "purifications" were performed by the city-state of Athens in an attempt to render the island fit for the proper worship of the gods; the first took place in the 6th century BC, directed by the tyrant Pisistratus who ordered that all graves within sight of the temple be dug up and the bodies moved to another nearby island. In the 5th century BC, during the 6th year of the Peloponnesian war and under instruction from the Delphic Oracle, the entire island was purged of all dead bodies.

It was ordered that no one should be allowed to either die or give birth on the island due to its sacred importance and to preserve its neutrality in commerce, since no one could claim ownership through inheritance. After this purification, the first quinquennial festival of the Delian games were celebrated there. Four years all inhabitants of the island were removed to Atramyttium in Asia as a further purification. After the Persian Wars the island became the natural meeting-ground for the Delian League, founded in 478 BC, the congresses being held in the temple; the League's common treasury was kept here as well until 454 BC. The island had no productive capacity for fiber, or timber, with such being imported. Limited water was exploited with an extensive cistern and aqueduct system and sanitary drains. Various regions operated agoras. Strabo states that in 166 BC the Romans converted Delos into a free port, motivated by seeking to damage the trade of Rhodes, at the time the target of Roman hostility.

In 167 or 166 BC, after the Roman victory in the Third Macedonian War, the Roman Republic ceded the island of Delos to the Athenians, who expelled most of the original inhabitants. Roman traders came to purchase tens of thousands of slaves captured by the Cilician pirates or captured in the wars following the disintegration of the Seleucid Empire, it became the center of the slave trade, with the largest slave market in the larger region being maintained here. The Roman destruction of Corinth in 146 BC allowed Delos to at least assume Corinth's role as the premier trading center of Greece. However, Delos' commercial prosperity, construction activity, population waned after the island was assaulted by the forces of Mithridates VI of Pontus in 88 and 69 BC, during the Mithridatic Wars with Rome. Before the end of the 1st century BC, trade routes had changed. Due to the inadequate natural sources of food and water, the above history, unlike other Greek islands, Delos did not have an indigenous, self-supporting community of its own.

As a result, in times it was uninhabited. Since 1872 the École française d'Athènes has been excavating the island, the complex of buildings of which compares with those of Delphi and Olympia. In 1990, UNESCO inscribed Delos on the World Heritage List, citing it as the "exceptionally extensive and rich" archaeological site which "conveys the image of a great cosmopolitan Mediterranean port". Iamblichus writes; the small Sacred Lake in its circular bowl, now intentionally left dry by the island's caretakers to suppress disease-spreading bacteria, is a topographical feature that determined the placement of

Colma Creek is a small creek that flows to the San Francisco Bay from its source in the Crocker Hills portion of San Bruno Mountain State and County Park, north of San Mateo County's Guadalupe Canyon Parkway, with contribution from April Brook on San Bruno Mountain proper, south of the Parkway. It flows southwest and makes a 90 degree bend in Daly City to flow southeastward, through Daly City and South San Francisco to the bay, its small delta is between the San Francisco International Airport. The creek has a tributary stream named Twelvemile Creek, which joins it from the southwest along Westborough Blvd. in South San Francisco. The large delta the creek once supported was an important stop for migratory waterfowl and other wildlife. However, like many urban creeks, Colma Creek has been surrounded by flood control walls, buried in some parts, had much of its large delta filled in by developers. Most of the lower parts of the creek are devoid of native vegetation due to the flood control project, reducing the habitat of the endangered California clapper rail and other species that use the creek.

The headwaters of the creek are lined with non-native trees like eucalyptus and Himalayan blackberry, displacing the native riparian plants like dogwood and willow. The creek sometimes runs dry due to the non-native vegetation lowering the water table at the source. In 2005, Shelterbelt Builders developed a habitat restoration plan to return the creek to its former state by removing invasive and non-native plants and replanting native, riparian plants at the source. In addition, in South San Francisco, new wetland was created to mitigate wetland lost to floodwall construction and improvements; the California clapper rail is expected to reinhabit the new salt and freshwater wetland, along with other species displaced by the flood control works. List of watercourses in the San Francisco Bay Area

The Apple II graphics were composed of idiosyncratic modes and settings that could be exploited. This graphics system debuted on the original Apple II, continued with the Apple II Plus and was carried forward and expanded with the Apple IIe, Enhanced IIe, IIc, IIc Plus and IIGS; the graphic modes of the Apple II series were peculiar by the standards of the late 1970s and early 1980s. One notable peculiarity of these modes is a direct result of Apple founder Steve Wozniak's chip-saving design. Many home computer systems of the time had an architecture which assigned consecutive blocks of memory to non-consecutive rows on the screen in graphic modes, i.e. interleaving. Apple's text and graphics modes are based on two different interleave factors of 8:1 and 64:1. A second peculiarity of Apple II graphics—the so-called "color fringes"—is yet another by-product of Wozniak's design. While these occur in all graphics modes, they play a crucial role in Hi-Res mode. Reading a value from, or writing any value to, certain memory addresses controlled so called "soft switches".

The value read or written does not matter. This allowed the user to do many different things including displaying the graphics screen without erasing it, displaying the text screen, clearing the last key pressed, or accessing different memory banks. For example, one could switch from mixed graphics and text to an all-graphics display by accessing location 0xC052. To go back to mixed graphics and text, one would access 0xC053. All Apple II machines featured an RCA jack providing a rough NTSC, PAL, or SECAM composite video output; this enabled the computer to be connected to any composite video monitor conforming to the same standard for which the machine was configured. However the quality of this output was unreliable. In addition to the composite video output jack, the IIc, IIc Plus, the IIGS featured a two-row, 15-pin output. In the IIc and IIc Plus, this connector was a special-purpose video connector for adapters to digital RGB monitors and RF modulators. In the IIGS it was an output for an analog RGB monitor specially designed for the IIGS.

Numerous add-on video display cards were available for the Apple II series, such as the Apple 80-Column Text Card. There were PAL color cards; some other cards added 80-column and lowercase display capabilities, while others allowed output to an IBM CGA monitor through a DE9 output jack. The Apple II video output is a monochrome display based upon the bit patterns in the video memory; these pixels are combined in quadrature with the colorburst signal to be interpreted as color by a composite video display. High resolution provides two pixels per colorburst cycle, allowing for two possible colors if one pixel is on, black if no pixels are on, or white if both pixels are on. By shifting the alignment of the pixels to the colorburst signal by 90°, two more colors can be displayed for a total of four possible colors. Low resolution allows for four bits per cycle, but repeats the bit pattern several times per low resolution pixel. Double high resolution displays four pixels per cycle. See the sections below for more details.

The blocky, but fast and colorful Lo-Res graphics mode was 40 pixels wide, corresponding to the 40 columns on the normal Apple II text screen. This mode could display either 40 rows of pixels with four lines of text at the bottom of the screen, or 48 rows of pixels with no text, thus two pixels, vertically stacked, would fill the screen real estate corresponding to one character in text mode. The default for this was 40×40 graphics with text. There are 16 colors available for use in this mode. Note that six of the colors are identical to the colors available in High-Resolution mode; the colors were created by filling the pixel with a repeating 4-bit binary pattern in such a manner that each bit group fit within one cycle of the colorburst reference signal. Color displays would interpret this pattern as a color signal. On monochrome monitors, or if the colorburst signal was turned off, the display would reveal these bit patterns. There are two equivalent; this mode is mapped to the same area of memory as the main 40-column text screen, with each byte storing two pixels one on top of the other.

The Lo-Res graphics mode offered built-in commands to clear the screen, change the drawing color, plot individual pixels, plot horizontal lines, plot vertical lines. There was a "SCRN" function to extract the color stored in any pixel, one lacking in the other modes. A block of 128 bytes stores three rows of 40 characters each, with a remainder of eight bytes left after the third row is stored, but these bytes are not left empty. Instead, they are used variously by motherboard firmware and expansion card firmware to store important in