For most developers these concepts aren’t that complicated and are widely used in the project they are working on. However, I do remember that when getting my computer science degree there was no mention of either of these in any of the courses. The only time it was actually mentioned in a class was when a student was giving a presentation, but it never came up in the coursework. This is fine because a degree isn’t supposed to teach you everything, but it is still something to look into before you get a job because you will need to know these things. An API is a set of methods for interacting with an application. Essentially it is a way for you to access information about an application without having to know how the application works. This is done by giving people access to endpoints in an application. These endpoints are essentially URLs that access a certain method that a developer has set up in order to access information from the application. So you can use an endpoint to get data from an API and then use that data in whatever way you need. It is a really simple thing to learn, but can be easily overlooked. If interested then you can click here to get a little more in-depth view of an API.

Also if you have any questions just ask them in the comments.