Understanding Kilobytes, megabytes, etc

Q:
What’s with all the sizes I see? Kilobytes, megabytes, etc?

A:
File sizes tend to be one of the more perplexing issues for both the fledgling and intermediate computer user. So, we’ve put together a breakdown of the various file size “units” you may encounter.

Bit – The smallest unit in computing. It can have a value of 1 or 0. You’d be hard pressed to find a file size listed in bits.

Byte – A (still small) unit of information made up of 8 bits.

Kilobyte(KB) – A unit of approximately 1000 bytes (1024 to be exact). Most download sites use kilobytes when they give file sizes.

Megabyte (MB) – 220 bytes = 1,048,576 bytes or 1,024 kilobytes. Sometimes used to mean 1 million bytes.

Gigabyte (GB) – Approximately 1 billion bytes (1024 MB). Most hard drive sizes are listed in gigabytes.

OK, now for a little practical application.

A 3 1/2″ floppy disk holds 1.44 Megabytes (1,474 KB).

A CD Rom holds 650-700 Megabytes (though most programs you get don’t utilize the whole amount). This would be around 450 of those 3.5 floppies.

A 20 Gig hard drive will hold the same amount of info as 31 CD ROMs or 14,222 floppy disks.

It takes between 7-10 minutes to download a one megabyte (1024 KB) file using the average dial up internet connection.

A typical page of text is around 4KB.

To see the size of a given file, just right-click it (in Explorer or My Computer) and select Properties from the resulting menu (or Alt+ double click the file).

I know that even with the information above, it can still be confusing, so I thought I would compare these digital units of measure to some everyday objects. Just picture them being completely hollow so you can store information in them.

Bit – Let’s call this a regular sized marble.
Byte – Compared to the marble, this would be a baseball.
Kilobyte – Now we jump up to a pickup truck size.
Megabyte – Now for the leap – this would be a medium sized sky scraper.
Gigabyte – Take 1024 of the medium sized sky scrapers and stick them together for this one!

Well, hopefully that helps 🙂

~ Steve