Data file in the context of Video compression

In 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. Typically, a device that performs data compression is referred to as an encoder, and one that performs the reversal of the process (decompression) as a decoder.

The process of reducing the size of a data file is often referred to as data compression. In the context of data transmission, it is called source coding: encoding is done at the source of the data before it is stored or transmitted. Source coding should not be confused with channel coding, for error detection and correction or line coding, the means for mapping data onto a signal.

A computer font is implemented as a digital data file containing a set of graphically related glyphs. A computer font is designed and created using a font editor. A computer font specifically designed for the computer screen, and not for printing, is a screen font.

In the terminology of movable metal type, a typeface is a set of characters that share common design features across styles and sizes (for example, all the varieties of Gill Sans), while a font is a set of pieces of movable type in a specific typeface, size, width, weight, slope, etc. (for example, Gill Sans bold 12 point). In HTML, CSS, and related technologies, the font family attribute refers to the digital equivalent of a typeface. Since the 1990s, many people outside the printing industry have used the word font as a synonym for typeface.

In metadata, the term data element is an atomic unit of data that has precise meaning or precise semantics. Data elements usage can be discovered by inspection of software applications or application data files through a process of manual or automated Application Discovery and Understanding. Once data elements are discovered they can be registered in a metadata registry.In the areas of databases and data systems more generally a data element is a concept forming part of a data model. As an element of data representation, a collection of data elements forms a data structure.