Pidgin (formerly named Gaim) is an open-source multi-platform instant messaging client, based on a library named libpurple. Libpurple has support for many commonly used instant messaging protocols, allowing the user to log into various services from one application.
The number of Pidgin users was estimated to be over 3 million in 2007.
How enable spell checking in pidgin:
To enable spell checking in pidgin you need to install aspell software.
If you want to enable English spell checking in pidgin just install aspell-en as shown below.
$ apt-get install aspell-en (it works in Debian/Ubuntu based OS)
After installing aspell you need to change some preferences in pidgin.
Open pidgin go to Tools –> Preferences –> Conversation Tab
Here you need to tick/enable Highlight misspelled words.
Now just restart pidgin, that will enable spell checking.