Bits are 1s or 0s representing the state of a switch, in binary form.
A byte is a binary word, consisting of 8 bits.
8 bits equals one Byte.
1024 bytes equals one KiloByte (KB)
1024 KiloBytes equals one MegaByte (MB)
1024 MegaBytes equals one GigaByte (GB)
Sometimes people use 1000 instead of 1024, so numbers sometimes get screwy.
A bit is always represented by a small “b”, a Byte is always represented by a large “B”.
It is common practice to use bits in reference to interface speeds and bytes in reference to memory and storage capacities.
For example, a 56K modem. the 56K is Kb, not KB.