Bitmap Graphics: The information below illustrates bitmap data.
Bitmap images are a set of bits that form an image. The image comprises a matrix of individual dots or pixels which have their own colour illustrated using bits. Let's take a look at a classic bitmap image to illustrate the principle:
To the left you notice an image and to the right a 250 % enlargement of the top of one of the mountains. As you can notice, the image comprises hundreds of rows and columns of small parts which all have their own colour. One that component is termed as a pixel. The human eye is not able of seeing each individual pixel hence we perceive a picture along with smooth gradations.
Application of the image selects the number of pixels you require to find a realistic looking image.