provides a powerful file storage facility based on conventional 3.5" floppy dises.

Each disc consists of a thin sheet of plastic coated in a magnetic material, and

this is housed in a hard protective shell to prevent it from being damaged

during use. Files are recorded on the disc in a series of concentric rings called

tracks, each of which is divided up into 16 sectors:

The discs used in your computer have 80 tracks and are double-sided (i.e.

both sides of the disc are used to store information) and the computer reads

them with a device called a disc drive. The disc drive rotates the disc at a

precisely regulated speed between the read/write heads which alter the

magnetic properties of parts of the disc in order to store information. When

both sides of the disc are used each disc will store about 640K bytes.

The computer is normally supplied with one disc drive, mounted on the

left-hand side of the case, which is referred to as 'drive 0'. You may wish to

purchase a second drive, mounted on the right, from your Acorn dealer. This

second drive is referred to as 'drive 1', and you are only likely to need it if you

expect to be working with very large amounts of information.

You will also have one disc, the Welcome disc, which contains numerous

example programs and utilities. If you look closely you will see a couple of

important features:

-- There is a protective metal shutter along one edge of the disc, which keeps

dust out when the disc is not in use. If you gently slide it sideways you can

see the disc itself inside but be careful not to touch it.

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