Every JavaScript function has a context. If you're coming from an object-oriented language, the function context is a lot like the object a method belongs to. The difference of course is that JavaScript doesn't classify objects in the object-oriented sense of the concept. Instead, functions are bound to a default context, and this can easily be changed at runtime. There are even built-in language mechanisms to make this happen.

Lo-Dash makes changing function contexts easy. We'll need to work with function contexts often when programming with Lo-Dash. We'll take a look at a number of approaches to working with and changing the context of functions now.