An installer is software that places an application's files in the right locations, creates shortcuts or services, writes settings, and makes the program removable later. Examples are .msi and .exe on Windows, .dmg and .pkg on macOS, and .deb and .rpm on Linux.
Why it matters
A good installer makes setup repeatable and reversible. Linux package managers act as installers that also resolve dependencies and deliver updates. Downloading installers from unofficial sites is a common route for malware.
On servers, installation is usually scripted so every machine ends up identical.
Example
$ sudo apt install ./app_1.4.2_amd64.deb
$ sudo apt remove appThe package manager installs the file and later removes it cleanly.
Common mistakes
- Skipping verification of the download checksum or publisher signature.
- Clicking through extra offers bundled in a free installer.
- Deleting an app's folder by hand instead of using its uninstaller.
Related
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