Some storage media can only store a very limited amount of data, whilst others can store vast amounts...
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Data storage capacity is measured in bytes (B).

A thousand bytes is known as a kilobyte (kB)
1,000B = 1kB

A million bytes is known as a megabyte (MB)

1,000,000B = 1MB

A thousand million bytes is called a gigabyte (GB)

1,000,000,000B = 1GB

A million million bytes is called a terabyte (TB)

1,000,000,000,000B = 1TB
Even a very basic storage devices like a floppy disc can storage over a megabyte of data - that's over 1 million letters or numbers!

And modern hard drives can store a terabyte of data or more - that's more words than you could type even if you started now, and typed until your old age!
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