Schematic capture is the process of creating your design inside your EDA software. This is the first step most people think of when it comes to design. But as this course has shown, schematic capture is closers to step four or five than it is to step one.
Let's take a moment to back up.
Several weeks ago, we began with a block diagram. At the time we also presented a complete schematic and parts list. When designing your own project, you won't have the schematic and parts list that early in the design process. But you will have the block diagram that you drew and access to application notes/datasheets/etc... that will hopefully provide sufficient information to allow you to build each of the blocks in your diagram. In schematic capture, you will input all of the information you've collected (part numbers, component symbols, associated land patterns) into a single schematic document.