>"If your terminal window is getting cluttered and you'd like to start from fresh, you can type clear. This will clear your window as if you've just reopened Terminal."

No, it won't. It only looks like it's like reopening the terminal, it won't reload your configs and stuff. Instead of writing "clear", you can do ctrl + r to achieve the same thing.

If you instead really want your terminal to be like reopened, do "reset" instead.

Regarding the history command, combining it with grep is when it becomes really useful. Example, all my latest git commands:

history | grep -i "git"