Utility software helps maintain the system. Utility software is used for:
Most basic utility software is part of the operating system, but additional utilities can also be installed separately.
There are several functions that can be used to manage files. These include the following.
Files can be corrupted due to:
A corrupt file can sometimes be repaired, and most operating systems have this utility. Another utility can detect and, if possible, recover from physical errors on the disk. It scans disk surfaces for defects and marks those sections as unavailable to prevent the rewriting of data and data loss.
It is sensible to always make a backup of files in case they cannot be recovered.
A file conversion utility lets users save a file as a different file type. This is useful, for example, when:
Compression software reduces the size of a file stored on secondary storage.
Smaller files are easier to transmit across a network as they require fewer packets to be sent. Their reduced size also means more files can be stored in any given area of storage.
When a file is stored on a hard disk it is not stored as a whole file, but as a series of segments. Sometimes the segments run together in sequence (see File 1) and sometimes the segments are split up over a disk (see File 3). This is known as fragmentation.
Over time, more and more files become fragmented. A fragmented disk takes longer to read from and write to, making a computer run slower.
Defragmentation software takes the fragmented files and rearranges the segments so that they run contiguously. This decreases read/write time, thereby speeding up computer performance.
Data can be lost accidentally or deliberately. A user may accidentally delete or overwrite a file or a hard disk may fail, preventing access to any files stored on it. A hacker or malicious user may deliberately delete or overwrite data.
To prevent data loss, regular copies of the data should be made. A copy of data is known as a backup. Backups can contain a copy of all files on a computer, or just those specified by a user.
Network managers make regular backups of all files on a network using backup software. The software automatically makes a backup at a scheduled time of day, usually during the evening when the network is quiet. Backups are usually made to a high capacity secondary storage device or to the cloud.
If data loss occurs, data can be retrieved from the backup. The software allows all backed-up files to be retrieved, or just specified files. This can be done with a system restore.
Two types of backup are possible:
A full backup involves making a copy of every file on the computer or network. This can require a lot of storage space and can be time consuming to make.
Incremental backups take a copy of any new files created since the last backup and of any files that have been edited, such as user documents.
Most network managers make an initial full backup and then switch to daily incremental backups. This way all data is backed up and daily backups are small and less time consuming.
Anti-virus software scans a computer system, either when activated or automatically at a specified date and time, and identifies potential viruses. Many anti-virus software programs can also delete or fix potential threats once they have been identified.
Spyware is installed on a computer without the knowledge of the user. It is usually designed to collect data about the user, often personal information or bank details, which can then be passed on and used in identity theft. Anti-spyware software can find, then delete, the spyware. Some versions can prevent it being installed in the first place.