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What are BYTES? What does "kilobytes" mean? How big is a megabyte? etc...

Computer lingo has become commonplace and yet it's just assumed that everyone knows what the terms such as "kilobytes", "megabytes", etc mean! I have found that (surprising as it may seem), although computer experts have a clear logical interpretation about the exact meaning of these terms, many people have no idea at all (2005/09), or they know in principle that "megabytes" are a about a thousand times bigger than "kilobytes", but further than that it's beyond weighing-up. If asked "What does that mean? How big is a megabyte really then? Will THIS BOOK fit into so-many megabytes on your computer hard disc drive?" it's rare to find anyone who has a realistic familiarity as might be found if "gallons" or "litres" were being talked about.

So here it is: A realistic explanation of what BYTES and KILOBYTES are, and how they relate to things in the actual world:

As a very rough estimate, a big weighty book such as the Complete Works of Shakespeare, or the Bible, or Hutchinson's Encyclopaedia of the World, is typically about 5 or 6 megabytes.

Megabytes are about a million bytes, or to be more precise, a megabyte is usually assumed to be 1048576 bytes.

So, what are BYTES? A byte is a single character, such as a number or a letter or a symbol or a space, any character. Take a look in a book and count the characters (including spaces) and that's how many bytes the book is. If a page has a thousand characters on it, then it's about a kilobyte (1024 bytes). On a keyboard, type a file consisting of "the quick brown fox jumps over the lazy dog" and that's 43 bytes (yes, spaces count as bytes too).

You can use a cunning shortcut method to count approximately how many bytes (characters) there are in a book. You can try this on just about any text book. See the method for finding how many bytes are in a book (generally takes about 5 minutes, or less, even for a big book!).

So, if you've bought a new computer with so-many gigabytes of hard disc and you've wondering if your memoirs will fit on it, or your website will take up much space, it's worth knowing that a gigabyte is over a thousand megabytes, and after a while you can get a weighing-up idea of how many gigabytes the mobile library truck is carrying around.

Other notes: A picture tells a thousand words, but a digital photo stored on a computer can take more room than a thousand words of storage. How much space depends on how big the photo is and how it is compressed. Some photos taken with a high resolution camera can take up as much an encyclopaedia of text.

Music stored on computers takes up a lot more space than text. A three minute single takes as much as a stack of books as a .wav file but can be compressed into mp3 or Ogg Vorbis and then only takes as much as a large book.

Ogg Vorbis is like mp3 only better, more efficient, free open source, and generally ignored.

Text can be stored in a compressed form too. Ratios of 7:1 are not uncommon.

Many amazing old books are available free as downloads from Project Gutenberg. You can get thousands of books on a modern computer without it taking up more than a small share of a hard disc drive.

A CD can store about 650 megabytes. A DVD is about 4 gigabytes. That's a lot of books worth!

Also see megabytes, gigabytes, terabytes

As well as data compression, where files take up less space than they would do, there are also formats which perversely BLOAT files and make them take up far more space than they should do. For example, dot doc files are often absurdly overinflated for no apparent good reason. Sending these by e-mail wastes time, money, and bandwidth.

To tell how full a hard disc drive is, in Windows you right-click on the drive icon and do "properties" and the machine shows you a pretty pie-chart. In Linux you just type in "df" and it just tells you the status of all the drives.

Floppy discs (3.5in) can hold 1.44 megabytes, which is enough to store a book, assuming it's not a huge book! See alternative portable hard disc drives for transporting more. This is being updated all the time, and "pen drives" can hold much more copious amounts of data. See memory shops

The term "BYTES" is made to sound like a variant of "BITS". A byte is made up of 8 bits. A bit is a state of a switch (on or off), represented by 1 or 0, with only two states. For a byte with 8 bits there are 256 possible combinations. For example, the character "*" is number 42 of (0-255), and has a code of 00101010. See a full list of ascii codes

Useful? Helpful? [response]. There are loads of other interesting pages like this. Well worth having a browse through the index to see what you can find!

Another thing which gets a page of helpful explanation because a surprising number of people don't know, is, Earth, Moon, and Sun, which orbits around which?