Is LISP popular? If Yes, Why?

I have been attending LISP classes since a month. I can't find anything that LISP does which other languages cannot. My professor tells LISP is a very efficient and well-used language. But I don't find any jobs that requires a LISP programmer(Everyone keeps talking about Java, C and C++, .Net etc). I searched many books to find what is differentin LISP. The books talk pages and pages about the importance of LISP without any clarity. The more I read, the more I get confused. Today if I get a chance, I will ask my professor regarding this. Hope he gives me a convincing reply.