Trilian is a software application designed for instant messaging and communication. It allows users to connect with multiple messaging services, such as AIM, MSN Messenger, and Yahoo Messenger, all in one platform. This makes it convenient for users to manage their conversations without switching between different applications. In addition to messaging, Trilian offers features like file sharing, voice chat, and customizable skins. It is available on various operating systems, including Windows, macOS, and Linux, making it accessible to a wide range of users. Trilian aims to enhance online communication by providing a unified interface for different messaging platforms.