Any information can be reduced to series of 0s and 1s, whether it's music a video film or a letter you type on the keyboard.

          As example a picture on the screen is devided into pixels which are small squares whose color can be defined by 3 numbers between 0 and 255 defining the level of mixture of 3 basic colors (red, green , blue). As it takes 8 bits to represent a number between 0 and 255 we can see that it takes 3x8=24 bits to describe the color of a particular pixel. If the resolution of your screen is 800x600 pixels, the number of bits theoretically used for a picture would be 800x600x24=11 millions and 520.000...

          Don't confuse bits and bytes. A "byte" is 8 bits. When you see "MB" (for megabyte), it means megabytes and not megabits.

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