What's the difference between APA and MLA?

There are many differences, but the biggest difference is in when each format is used. APA formatting is used for writing papers in the sciences and social sciences, while MLA formatting is intended more commonly for papers written in the humanities/liberal arts areas. As for the formatting itself, MLA formatted papers don't have a title page or abstract while APA papers do. In-text citations in MLA include author and page, while APA citations include author and date. There are differences in the titles and layouts of the reference lists for each type of paper. This is just a sampling, reviewing the style manuals for each will reveal many other differences.