Multimedia is communication that uses more than one type of information content (e.g. text, audio, graphics, animation, video) to inform or entertain the audience (user). "Multimedia" also means the use of electronic media to store and experience multimedia content.
Multimedia means that computer info can be represented through audio, graphics, image, video and animation in addition to traditional media (text and graphics).
Multimedia Making it Work, by Tay Vaughan, Published by Osborne McGraw Hill 1993
Shield volcano
A shield volcano is a large volcano with shallowly-sloping sides. The name derives from a translation of "Skjaldbreiður", an Icelandic shield volcano whose name means "broad shield," from its resemblance to a warrior's shield.
Shield volcanoes are usually formed by lava that flows easily. Consequently, a volcanic mountain having a broad profile is built up over time by flow after flow of relatively fluid basaltic lava issuing from vents or fissures on the surface of the volcano. Many of the largest volcanoes on Earth are shield volcanoes.
The largest is Mauna Loa on the Big Island of Hawaii. Shield volcanoes can be so large they are sometimes considered a mountain range, such as the Ilgachuz Range and the Rainbow Range, both of which are in Canada. These shield volcanoes formed when the North American Plate moved over a hotspot similar to the one feeding the Hawaiian Islands, called the Anahim hotspot. There are also shield volcanoes, for example, in Washington, Oregon, and the Galapagos Islands. The Piton de la Fournaise, on Réunion Island, is one of the more active shield volcanoes on earth, with one eruption per year on average.
Shield volcanoes are known to form on other planets. The largest known mountain in the solar system, Olympus Mons on Mars, is a shield volcano. Shield volcanoes on Mars are higher and much more massive than those on Earth.
On Earth, because of plate tectonics, hotspot volcanoes eventually move away from the source of their magma and the volcanoes are individually less massive than might otherwise be the case. Shield volcanoes usually occur along constructive boundaries or above hotspots. However, the many large shield volcanoes of the Cascade Range of northern California and Oregon are over a more complex environment.
Caldera
A caldera is a volcanic feature formed by the collapse of land surface after a gigantic volcanic eruption. In such an eruption the volcano's magma chamber is empty enough for the ground above it to drop.
A caldera may look like a volcanic crater except that a crater is made by blasting outward, not by collapsing inward. The word "caldera" comes from the Portuguese language, meaning "cauldron". Some complex features are made by both processes.
When Yellowstone Caldera last erupted some 650,000 years ago, it released about 1,000 km of material, covering much of North America in debris up to two metres thick. By comparison, when Mount St. Helens erupted in 1980, it released 1000 times less material.
The ecological effects of the eruption of a large caldera can be seen in the record of the Lake Toba eruption in Indonesia.
About 75,000 years ago, the Toba catastrophe released about 2,800 km of ejecta. This was the largest known explosive eruption within the last 25 million years. In the late 1990s, anthropologist Stanley Ambrose suggested that a volcanic winter induced by this eruption reduced the human population to about 2,000 20,000, resulting in a population bottleneck. Others suggested that the human race was reduced to about five to ten thousand people.
However, there is no direct evidence that the theory is correct and some evidence that it is not.
Eruptions forming even larger calderas are known. At La Garita Caldera in the San Juan Mountains of Colorado, the 5,000 km Fish Canyon Tuff was blasted out in a single major eruption about 27.8 million years ago.
At some points in time, rhyolitic calderas have appeared in distinct clusters. The remnants of such clusters may be found in places such as the San Juan Mountains of Colorado (formed during the Oligocene, Miocene, and Pliocene periods) or the Saint Francois Mountain Range of Missouri (erupted during the Proterozoic).
Addiscombe
Addiscombe is a area in Croydon, in the London Borough of Croydon, England. Three hundred years ago, Addiscombe was a rural area. The area was mainly used for farming and brick-making. There used to be a railway that went through Addiscombe, but in 2000, it was changed to tramlink tracks and a new stop was built.
South Norwood
South Norwood is an area in south-east London in the London Borough of Croydon, England. It is one of four places in London called Norwood, Norwood New Town, West Norwood and Upper Norwood are the others. There are around 14,590 people living in South Norwood alone. SE25 is the postcode for the area.
Norwood Junction train station is the station which serves most of South Norwood, to Central London. There are two secondary schools in South Norwood called, Harris Academy South Norwood (was Stanley Technical High School) and the other being Harris Academy Crystal Palace. There are also a lot of primary schools in the area.
The writer of the Sherlock Holmes stories lived in South Norwood on Tennison Road from 1891 to 1894. One of his stories was about the area. In 1966, a dog called Pickles discovered the World Cup Jules Rimet Trophy under a bush farther up in Beulah Hill.
South Norwood Country Park is a large green space and nature reserve in South Norwood, it was the site of a former sewage farm which was made for the growing population of London. Croydon Sports Arena which holds games for Kent League team Croydon Football Club "(Croydon F.C.)". Crystal Palace F.C. play at Selhurst Park in Norwood. The team, for the 2007-08 season are in the Championship.
Software bug
A software bug is a problem with the code in a computer program which makes it not work properly. They can cause inconvenience to the user and may make their computer crash or freeze. Most computer programs have bugs. A program that has a large number of bugs (or possibly a single or a few serious bugs) is said to be buggy.
Most bugs are caused by bad programming by the developer, but sometimes they can be caused by compiler problems. When bugs are found, people send bug reports to the developer to tell them about the bug and let them fix it.
Sometimes, people say that their computer has a bug when something is wrong with it. The problem is usually caused by a computer virus which has infected their computer and is making it slow or do different things.
Some bugs are harmless, for example, many video games incorrectly allow objects to move through walls. Other bugs are more severe, for example, a bug in a navigation system that causes an airplane to explode.
A buffer overflow happens when a program writes to or reads from an area of memory that it is not supposed to access.
An arithmetic overflow happens when a number contained in a variable is increased beyond the highest number that the variable allows. This will usually cause the number to reset back to zero.
An infinite loop happens when a program enters a loop (a series of instructions that is repeated many times) and there is no way out of the loop. This can cause the program to freeze.
If a floating point variable doesn't have enough precision, the number stored in it can be inaccurate. This can cause various problems depending on the type of program, for example it could cause a navigation program to navigate to an unintended location, or distorted sound in an audio recording program.
Division by zero is an invalid math operation. If a program divides an integer by zero, it will crash. On Linux, the message displayed when this bug occurs is "floating point exception", even though floating point numbers were not involved. Floating point math sometimes allows division by zero. This will usually result in a special "not a number" value.