(a) List three criteria that are used in classifying file. (b) State: (i) two advantages and two disadvantages of computer files; (ii) three methods of file...

(a) Three criteria used in classifying files

1. Nature / purpose of the file (for example master file, transaction file, reference file, backup file).
2. Organisation or method of access (serial, sequential, indexed-sequential or random/direct access).
3. Type of content or storage medium (for example text, program, data or graphic files; or the medium such as disk or tape file).

(b)(i) Advantages and disadvantages of computer files

Two advantages:

1. Large volumes of data can be stored in a small space and retrieved quickly.
2. Files can be easily updated, sorted, copied and shared, and they reduce paperwork.

Two disadvantages:

1. Files can be lost or corrupted through virus attack, disk failure or power problems.
2. Data in files can be accessed or altered by unauthorised persons if not properly secured, and recovery may be costly.

(b)(ii) Three methods of file security

1. Use of passwords and access rights so that only authorised users can open or edit the file.
2. Encryption of the file so that its contents cannot be read without the key.
3. Regular backup of files (and use of anti-virus software / write-protection) so that data can be restored if the original is lost.