Data storage: bits, bytes, kilobytes, megabytes, and gigabytes
OK - let's start from the beginning. EVERYTHING stored on a computer ends up as a little switch being either on or off (1 or 0). EVERYTHING. Let me repeat: EVERYTHING. Early programmers programmed in binary - basically, ones and zeros. Eventually, people built up enough code that programmers could work more abstractly - say, with words or objects on screen - however, it all boils down to those little ones and zeros.
The information stored on a single switch is called a 'bit'. There are two possible values - one and zero. This is pretty limiting, let's face it.
Therefore, the basic unit of storage, effectively, is a 'byte' - a byte is a series of 8 bits.
In the next section, we will go into this 'byte' in a bit of detail. However....
bit: One on/off switch (or think of it as a one/zero)
byte: 8 bits
kilobyte (KB): 1024 bytes - however, think of this as, effectively, 1000 bytes). Why 1024, you ask? because that's 2 to the 10th power (2x2x2x2x2x2x2x2x2x2). Remember, everything in a computer works on this 2 to a power thing. It all comes back to that 1/0 bit thing.
Megabyte (MB): 1024 kilobytes. Think 1000 again.
Gigabyte (GB): 1024 megabytes. Getting the pattern?
Terabyte (TB): 1024 Gigabytes.... So far, no-one is worrying about the next step. Whatever that may be. Now, go back a lesson and take a look at mass storage and how much they store.