For real? I absolutely had that one backwards too. Thanks 
That one’s easy. If you have something big or that is likely to change, instead of passing an unchanging copy of it, you pass a pointer to it, so that anything using it gets the most up to date version, plus doesn’t create another copy of it in memory. The best example is if you have a bunch of objects and want to make a list out of them, the list is just a list of memory address pointers, rather than a new copy of each object.
You will use them all the time, so it’s best to understand them. Heck, I got by with not even understanding the right dereferencing symbol, so they’re not that hard once you know what they are.