 In this section, we're going to build an actual processor. It's going to be a really simple processor, but it's going to have everything we really, really need. This processor will support six different instructions that will cover all of the basic things we're really interested in. We have add, add immediate, load word, store word, branch equals and jump. These would allow us to build reasonably complex programs, but we'll also see that this architecture is reasonably extensible. It won't be too hard to add additional instructions to this. We've already seen that subtraction is not too much different from addition. We really just need to ask our ALU to do the subtraction operation instead of an addition operation, so that operation would be really easy to add. Others will require a little bit of additional hardware, but they're not going to straight far from this architecture. We'll be building this architecture using the pieces that we've already seen. We've already seen how to build ALUs, multiplexers and memory structures, and that's going to form the bulk of this architecture. This is called a single cycle architecture because we'll see in the next section that this isn't a terribly efficient architecture. This architecture is only as fast as the longest instruction. All of our instructions will be required to take the same amount of time, and this won't be terribly efficient. So in our next section, we will look at a multi-cycle architecture which will improve upon this.