Is there an official Catholic website?

catholic.com is a site built to help Catholics defend their faith by providing answers to every expected questions about Catholicism. Catholic Answers is a media ministry that serves Christ by explaining and defending the Catholic faith.

What is the difference between Catholic and Roman Catholic?

When used in a broader sense, the term Catholic is distinguished from Roman Catholic, which has connotations of allegiance to the Bishop of Rome, i.e. the Pope. They describe themselves as Catholic, but not Roman Catholic and not under the authority of the Pope.