So there are eight important types of purification processes that you should be familiar with. So in this lecture, we're simply going to go through these processes quickly. But in the next several lectures, we're actually going to discuss them in much more detail. So we have eight processes. We have dialysis. Now, the thing about dialysis is it doesn't actually allow us to separate different proteins, but what it allows us to do is it allows us to separate the proteins from other small molecules and ions by using a semipermeable membrane.