In this scenario, they are the same. The category.this syntax is helpful If you have a non-static nested course that should check with its outer class's instance. In Java, this is often a reference variable that refers to the current object on which the method or constructor is becoming invoked. https://franciscosnfxm.p2blogs.com/32001694/the-smart-trick-of-free-this-jav-that-no-one-is-discussing