We all end up flushing our toilet a few times each day. You might not even be aware you are doing it, but if you pay attention, you might be surprised at the number of times you end up pulling that lever. Considering how often it is used, it is pretty amazing that your toilet handle holds up as well as it does, but there are times when these fail.
The functionality of a toilet is pretty basic. While there are some variations on the flushing mechanism, the tried and true method is by having a chain from the handle connected to a flapper that opens and closes to flush. Replacing a failing toilet handle is a fairly easy job if you want to take care of it yourself.
There is usually a nut inside the tank behind the handle holding it in place. Removing this and the chain to the flapper, you can put on the new handle. Just be aware that you might need to adjust the length of the chain to ensure proper flushing.