Installers

An installer is a software program or a set of programs that guides the deployment of a software application or hardware driver onto a computer or device. Installers typically perform tasks such as copying files, configuring system settings, creating shortcuts, and ensuring that required prerequisites are present. They may also guide users through optional configuration steps and verify that the installation completed successfully. The term can also refer to professionals who perform the physical or software installation of systems in an organization.

In software distribution, installers are distinguished from package managers and repositories. Installers often provide a self-contained workflow with a user interface, while package managers rely on centralized packages and automatic dependency resolution. Installers may offer both graphical user interfaces and silent or unattended modes for automated deployment, which is useful in large-scale or repeatable environments.

Common types and features of installers include: graphical installers that present a guided setup, and silent installers that run without user interaction; platform-specific formats such as Windows Installer (MSI), NSIS, Inno Setup, and InstallShield; macOS package formats (PKG); and cross-platform or scriptable installers. Important features often include prerequisite checks, component selection, configuration options, logging, error handling, rollback and uninstall capabilities, integrity checks, and code signing for security.

The installer workflow generally comprises initialization, file deployment, system configuration (including registry or environment changes where applicable), post-install validation, and cleanup. Human installers, when involved, perform site preparation, hardware installation, and coordination with software setup to ensure proper integration into existing systems.