Bitmap - What does bitmap mean?
A method of creating, storing, and processing digital images. A bitmap is a rectangular grid of pixels. The most basic bitmaps are made of bits; a bit is a binary digit and is the basic unit of information in digital form. A bit represents one of two values (e.g. 1 or 0, black or white, yes or no, true or false etc). Pixels can be made up of more than one bit, and the number of bits per pixel determines the number of distinct colours (and therefore the depth of colour) that a single pixel can represent. Bitmap graphics represent images in the form of a grid that is made up of individual pixels or points of colour.
They are resolution dependent; when a bitmap image is created, it is made using a set number of pixels per inch (ppi). To increase the size of a bitmap, new pixels are added in but, because they don't have their own colour information, their colour is determined by copying the colours of the surrounding pixels. To decrease the size of a bitmap image, some of the original pixels must be lost. In both cases, the quality of the image is reduced.Go Back to Glossary