Why are TV Shows filmed with people laughing in the background?

Question

Why are they fillmed on a set infront of an audience?

Answer 1

People laugh more in an audience than by themselves.  Comedians know this, when you're in a room full of people you enjoy it more.  

I have seen comedy movies twice, once when I was nearly all by myself in a theater and then again with a theater full of 'cult' people for that particular director, and the difference was amazing.  It was like I didn't realize how funny the movie was the first time!

Some TV programs are filmed before a live audience for this reason. But even so, these days, the soundtrack is 'sweetened'.  When you see a 'reality-based' program like Dancing with the Stars or So You Think You Can Dance, you hear people cheering all through the numbers--you know the audience doesn't do that, that's added later.  And at the end you hear the cheering of many more people than there are in the studio.  It's just their way of making it 'more exciting' (though phonier).  TV sitcoms often have the same laugh after every line, even lines that aren't really funny at all.

A few times, sitcoms have experimented with laughtracks, so some episodes have them and some not.  Then they do some kind of market research to see which one got more people to watch the ads, because that's all they really care about.  8^)

Answer 2

Performers are sometimes sharper in front of an audience. In theater, you can rehearse a script for so long that you can forget that some lines were supposed to be funny or ever were funny.

It may be riskier for the performers, too. Although scenes can be re-taped, no performer wants a reputation for flubbing lines. But that risk, along with the audience, can gakvanize a performance.