Board Thread:Questions and Answers/@comment-6312663-20161027202453/@comment-16461120-20161104214540

A crossover is an event which occurs between two or more different comic titles. This can be between two or more MARVEL series like "Acts of Vengeance" where it's contained within a single publishing line, or between one or more MARVEL books and one or more books from a different publisher like "Amalgam Comics", etc.

A collection is a book which consolidates multiple issues, either from the same comic title or from the same event, into a single reprint publication.