A byte is a unit of measurement for digital information in computing and telecommunications. Each byte is broken up into 8 bits as a de facto standard, though it can range from anywhere between 4 and 40 bits per byte depending on the hardware. Each bit denotes the binary value of 0 or 1.
For larger units of measurement for bytes, keep in mind that they do not use a decimal increase but instead a binary increase. A single KB, or kilobyte, equals 1024 bytes. A MB, or megabyte, equals 1024KB or 1,048,576 bytes. A GB, or gigabyte, equals 1024MB or 1,073,741,824 bytes. A TB, or terabyte, equals 1024GB or 1,099,511,627,776 bytes.
For bits, it is slightly different in the fact it uses the decimal increase instead of the binary increase. A Kbit, or kilobit, equals 1000bits. A Mbit, or megabit, equals 1000Kbits or 1,000,000 bits. A Gbit, or gigabit, equals 1000Mbits or 1,000,000,000 bits. A Tbit, or terabit, equals 1000Gbits or 1,000,000,000,000 bits.
As you can see, the difference in increase between a byte and a bit ends up getting larger and larger as the prefix increases the value. As we continue finding ways to make data storage more compact, the sizes will increase even more exponentially until we will have ZB, or zettabyte, hard drives that hold 1,180,591,620,717,411,303,424 bytes! Now thats a lot of data!