An installation software (sometimes also referred to as an installer software or setup tool) is a tool that install files and configures settings in a computer's operating system. The installation process in an operating system can sometimes be very complicated because different operating systems (OS), different bitness (32 or 64 bit), client or server computers must be handled by same setup program.

A good installation software must also handle the following (if needed):

• Check that the system requirements for the software to install are met

• Ask for a license key and verify that it is correct

• Update files if the software already has been installed once

• Add shortcuts to programs and documents in the user interface of the OS

• Add data folders to the system

• Register a user or activate a product

An easy-to-use user interface is important

The computer skills of the end-user can vary a lot. That's why it is so important that the user interface of the setup program is easy-to-use. Although the installation process itself can be quite complicated, the end-user should never notice this. Ideally, the end-user should only specify a destination folder and a program group (shortcut group) for his/her installation. And in some circumstances, enter a license key during the setup.

Distribution via CD, DVD, USB flash drive or the Internet

Nowadays software can be distributed in different ways. It can be distributed psychically via a CD, DVD or USB flash drive, or electronically via the Internet. In the past distribution via a CD or DVD were very common, but nowadays many software developers (and their customers) prefer distribution via the Internet. A good installation software should always handle this in a proper way.

Multiple languages support

The world has come more international. Companies sell software to other countries, but not everybody masters English. So many software developers create localized version of their applications, so for example a Spanish-speaking person can get the software in Spanish. For this reason also the installation software must be able to create a setup interface in Spanish, or other language. An intelligent setup tool can change language automatically, so the same language is used in the setup program as in the operating system.

Code signed setup packages

Security is getting more and more important. To prevent that somebody manipulate an installation after distribution, the setup package should always be code signed. By code signing a setup package, it is almost impossible to make changes in the setup file without it is discovered by the operating system. An advanced checksum system is used to detect unwanted changes. Most setup tools can code sign a setup package automatically, although there are separate tools available that can code sign the package afterwards.

Installation software on the market

There exists lot of installation software on the market that can create a setup package for different operating systems and hardware system. One example of such installation software is Visual Installer from SamLogic. Visual Installer is a versatile setup tool that can create setup packages for the Windows operating system.