Is there any real significant difference between Protestantism and Catholicism? I know a lot of people who have very strong views against Catholics and was really starting to wonder, just as the title suggests, other than Catholicism having priests, what differences are there?
The question makes the assumption that "Protestantism" is easily defined, and can easily be compared.

"Protestant" simply means "Not Catholic or Orthodox", and could refer to one of hundreds of different denominations, all with subtle and not-so-subtle differences in beliefs.  Some hold doctrine that is similar to Catholic doctrine, and some that is vastly different.

There's a comparison chart of Catholic to Protestant views here, but as I said in the above paragraph, on the Protestant side, there are a wide range of beliefs, and this chart only shows one particular protestant view.  (Glancing at it, it appears to be a Calvinistic point of view.)

An entire book could be written on this subject alone, but some differences include:


In general, Protestant Churches adhere to the concepts of Sola Fide and Sola Scriptura.  These are probably the biggest differentiating beliefs, but even they are not universall held by protestant denominations.
The Catholic Church includes Apocryphal writings as part of their accepted Scripture.  This includes a few extra books to the Bible, and two extra chapters to the Book of Daniel.
The Catholic Church accepts the concept of Purgatory, which is almost universally rejected in protestant denominations.  The same can be said for Transubstantiation, indulgences, prayer to saints, confession to a Priest rather than direct confession to God through prayer, and a host of other teachings.


In general, your question can be answered as "yes, there are some significant differences between Catholicism and Protestantism", but the difference varies based on which Protestant denomination you're referring to.