Data compressionIn information theory, data compression, source coding, or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless. Lossless compression reduces bits by identifying and eliminating statistical redundancy. No information is lost in lossless compression. Lossy compression reduces bits by removing unnecessary or less important information.
Lossy compressionIn information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size for storing, handling, and transmitting content. The different versions of the photo of the cat on this page show how higher degrees of approximation create coarser images as more details are removed. This is opposed to lossless data compression (reversible data compression) which does not degrade the data.
Image compressionImage compression is a type of data compression applied to s, to reduce their cost for storage or transmission. Algorithms may take advantage of visual perception and the statistical properties of image data to provide superior results compared with generic data compression methods which are used for other digital data. Image compression may be lossy or lossless. Lossless compression is preferred for archival purposes and often for medical imaging, technical drawings, clip art, or comics.
Rate–distortion theoryRate–distortion theory is a major branch of information theory which provides the theoretical foundations for lossy data compression; it addresses the problem of determining the minimal number of bits per symbol, as measured by the rate R, that should be communicated over a channel, so that the source (input signal) can be approximately reconstructed at the receiver (output signal) without exceeding an expected distortion D. Rate–distortion theory gives an analytical expression for how much compression can be achieved using lossy compression methods.
Word (computer architecture)In computing, a word is the natural unit of data used by a particular processor design. A word is a fixed-sized datum handled as a unit by the instruction set or the hardware of the processor. The number of bits or digits in a word (the word size, word width, or word length) is an important characteristic of any specific processor design or computer architecture.
Fifth generation of video game consolesThe fifth generation era (also known as the 32-bit era, the 64-bit era, or the 3D era) refers to computer and video games, video game consoles, and handheld gaming consoles dating from approximately October 4, 1993, to March 23, 2006. For home consoles, the best-selling console was the Sony PlayStation, followed by the Nintendo 64, and then the Sega Saturn. The PlayStation also had a redesigned version, the PSone, which was launched on July 7, 2000.
Convenience storeA convenience store, bodega, convenience shop, corner store or corner shop is a small retail store that stocks a range of everyday items such as coffee, groceries, fruits, vegetables, snacks, confectionery, soft drinks, ice creams, tobacco products, lottery tickets, over-the-counter drugs, toiletries, newspapers and magazines. In some jurisdictions, convenience stores are licensed to sell alcoholic drinks, although many jurisdictions limit such beverages to those with relatively low alcohol content, like beer and wine.
Sixth generation of video game consolesIn the history of video games, the sixth generation era (sometimes called the 128-bit era; see "bits and system power" below) is the era of computer and video games, video game consoles, and handheld gaming devices available at the turn of the 21st century, starting on November 27, 1998. Platforms in the sixth generation include consoles from four companies: the Sega Dreamcast (DC), Sony PlayStation 2 (PS2), Nintendo GameCube (GC), and Microsoft Xbox.
Grocery storeA grocery store (AE), grocery shop (BE) or simply grocery is a foodservice retail store that primarily retails a general range of food products, which may be fresh or packaged. In everyday U.S. usage, however, "grocery store" is a synonym for supermarket, and is not used to refer to other types of stores that sell groceries. In the UK, shops that sell food are distinguished as grocers or grocery shops (though in everyday use, people usually use either the term "supermarket" or a "corner shop" or "convenience store").
64-bit computingIn computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit CPUs and ALUs are those that are based on processor registers, address buses, or data buses of that size. A computer that uses such a processor is a 64-bit computer. From the software perspective, 64-bit computing means the use of machine code with 64-bit virtual memory addresses.
