Plugins (add-ins) are very popular nowadays. A plugin is an stand-alone module that adds its services to the application only when these services are needed. The biggest advantage is the stand-alone feature. Everyone can make his/her own plugin if the plugins interface is public. For example someone will make a plugin for viewing avi files (popular video format) and you'll be able to easily view avi files directly from Altap Salamander - you'll just add this new plugin to your installed Altap Salamander. Another big advantage of the stand-alone feature is that adding functions doesn't affect the file size of the main executable. So Altap Salamander will start just as fast even when it contains many new functions (using plugins). Plugins are loaded into memory only when they are needed and they can be unloaded from memory after use.