You can clone with
Don't defer explanations: Either explain here and now what in SDL/gaming context is
If necessary draw comparisons to non-game GUI programming and emphasize how they might differ.
If people start with game programming, the jargon and the underlying concepts are important to understand. They might come from a GUI programming background though and understand certain things better if you compare similarities and differences.
Example: "As you can see, SDL opens a simple window if you call App->new. This is not the same kind of window as you'd open with Gtk::Window->new, because SDL's "window" already come with a "surface" attached to them. The "surface" is - similar to many libraries you draw lines with - your canvas to draw your game magic on" ... something along those lines.