Explain the purpose of different software utilities

Security.

Here are some examples for security: Virus protection, Firewalls and drive formatting.

Virus protection.

You can get a virus in many ways such as a dodgy email or a dodgy website. Computer viruses are small software programs that are designed to spread from one computer to another and to interfere with computer operations. A virus might corrupt or delete data on your computer, use your e-mail program to spread itself to other computers, or even erase everything on your hard disk. Computer viruses are often spread by attachments in e-mail messages or instant messaging messages. That is why it is essential that you never open e-mail attachments unless you know who it's from and you are expecting it. Viruses can be disguised as 

attachments of funny images, greeting cards, or audio and video files.

Firewalls.

Firewall security software is one type of computer program that aims to protect a computer from computer viruses. A firewall monitors traffic coming into an operating system and helps stop harmful programs that attempt to gain access to the computer user's personal information or hinder the computer user's use of that computer. Typically, computers will not only have a firewall, but antivirus and antispyware software as well. Firewall security software can be purchased separately, though today, most operating systems have firewalls 

built in.

The firewall is usually located at the entry point of a network or individual computer. When Internet traffic accesses a computer, firewall security software is the first thing that receives it, and it is the last to handle outgoing traffic. When a user starts an Internet-related program, such as an online computer game, the computer connects to another website and sends information about the user’s computer system. Before accessing the computer, however, the data has to pass through the firewall. If the user has set the firewall to 
allow transfers of data to this site, the data will be processed through.

Drive formatting.

Before a magnetic disk can be used, it must be prepared for use. This process is called formatting. Formatting theoretically erases all data previously stored on a disk. Formats are specific to a disks operating system, for example a disk formatted for the use on a Microsoft Windows system will not read natively on an Apple Mac ( special drivers are required for this). Operating systems such as Microsoft Windows have GUI format utilities but can also perform the same process as the CLI. 

A disk format:

• ·         Prepares the physical locations ready for recording.
• ·         Sets up a filing system e.g. FAT on the disk.
• ·         Checks the disk for physical or magnetic errors.

What utility.
Norton utility does many things, this includes defragmentation and many clean up tools.

Defragmentation.
Most operating systems have disk filling systems which create fragmentation over time.
Fragmentation occurs when space reclaimed after a file id deleted, is used to store parts of a larger file. The end result is that a file does not exist in disk locations. Fragmented files are slower to load into RAM, simply because the hard drive has to work harder to physically locate and read the clusters which form the file. Most operating systems have a utility to defragment a file system. This utility may be run as an ad hoc (e.g. unplanned, whenever needed) process or on a regular schedule.

Clean up tools.
Most operating systems keep a detailed account of user activity. There are times when such accounts are not required. In order to manage such activity, most operating systems have options whether you want to remove personal information from the system. In the internet age, possibly the two most common footprints to erase are:

• Internet history.
• Cookies.
• Passwords.
• Information entered onto online forms.

These options will be located in the operating system or the internet client software.

In reality, formatting a disk clears the filing system’s ‘table of contents’; the data is still there but the Operating System will have no idea where the various files are physically stored. This means that data may still be recoverable using specialist data recovery software. Sensitive data (i.e. personal or business) should be safely deleted using data shredding software, the surest way to erase data is to physically destroy the disk itself.