In order to install new software on your computer, you often need to run an installer program. This program unpacks compressed data included with the installer and writes new information to your hard drive. While some installers do not use compressed data, most use some level of compression since it reduces the size of the files included with the installer. This is especially helpful when downloading programs or software updates from the Internet.
An installer can either install a new program on your computer or can update a program currently on your hard drive. It can also update or add files to your operating system. Most installers can be run by simply double-clicking the installer icon and then choosing the folder you want to install the software into. The nice thing about installers is that they do all the work for you, decompressing and writing the data on the hard drive. Once the installer is finished, you can often use the new or updated software right away. If any system files were installed, you will be asked to restart your computer before using the new software. This is because system files can only be loaded during the computer’s boot process.