Source Telegram Homepage.
The application features desktop notifications for incoming messages and supports file and photo sending, ensuring compatibility with any format, be it documents, archives, music files or pictures. And like in any messaging application out there, conversations can be enriched using various funny emoticons.
To install Telegram just run the following commands via your systems Terminal.
sudo add-apt-repository ppa:atareao/telegram
sudo apt-get update
sudo apt-get install telegram
That's all Enjoy!