An "Installer" is a software program or tool that helps set up applications on a computer or device. It guides users through the process of copying files, configuring settings, and ensuring that the software runs correctly. Installers can be found in various formats, such as Windows Installer or macOS Installer, and often include a user-friendly interface. Installers may also check for system requirements, ensuring that the hardware and software are compatible before installation begins. Some installers allow users to customize the installation process, such as choosing specific features or installation locations. This makes it easier for users to manage their software effectively.