Common Graphic File Formats for Images
From Free Knowledge Base- The DUCK Project: information for everyone
Windows Bitmap
The three most common bitmaps, 1, 8 and 24 bit bitmaps. The number of bits in a bitmap represents the possible number of colors the given bitmap can contain. This means that a 1-bit bitmap can have two possible colors, which are always black and white. The 1 bit bitmap is also known as a monochrome bitmap.
The 8-bit bitmap can contain up to 256 colors (2^8 = 256) and the 24-bit bitmap can have up to 16.7 millions colors (2^24 = 16.7 million). The value X-bit defines the size of each pixel in a bitmap. So an 8-bit bitmap with a width of 100 and a height of 200 takes up 100*200*8 bit = 160 KBits = 20 KB.