Why Do Applications Need Installing? [closed]

Question

I'm confused. Right now I write some small apps using C++ and Java, but none of them need to be installed. Why do "big apps" like browsers, media players, games etc. need to be installed?

Answer 1

There are several reasons:

1. They hook into the system. When you install a browser, it will be started if you open a file which starts with "http://" or ends with ".html"

2. People using apps are used to install them. If your app doesn't come with an installer, users are confused how to get it up and running. They don't understand what happens during installation, they just know that they always have to do it. So some applications (which don't need installers) come with a simple installer just to avoid confusion.

3. A lot of complex applications can do things in various ways. You can change presets during the installation. A common example is which parts of the application to install. For a CAD system, you can install the whole thing or just a viewer for a PC in a meeting room.

4. Many apps ask for a license key and/or online authentication to avoid piracy.

5. Many apps come with DLLs. To make sure they work, they overwrite all DLLs in the Window's system directory (and possibly break all other apps but who cares ;-)

Answer 2

Typically, because they want to store state and information with the computer. For example, your application will not appear in the Add / Remove programs window. Many programs (which I personally dislike) like to store important information in the registry for lookups, which means you usually want an uninstaller (instead of just deleting the program) to do cleanup, or they might introduce extensions into explorer or other items. Simply deleting the program won't clear those additions, so you'd want an uninstaller.