What is the difference between that and 'Like'?
I would guess people use them differently than me, but I use "like" frequently to indicate I enjoyed a particular post or agree with what's stated, and I might "like" several posts by the same (or different) author(s) in a given thread. I "applaud" when someone is particularly generous with the forum, writes or contributes an especially entertaining or insightful way, helps someone. I would applaud a given author only once in a given thread. A like is polite clapping or agreement. Applause is a standing ovation or recognition of selfless generosity.