For a lot of more advanced cooking, you need to be able to separate eggs. You separate eggs by separating the yellow yolk part from the transparent “white” part. (The white is the part that would turn white if you cooked the egg). You need to separate eggs so you can beat the egg whites. Then you can make souffles or chocolate mousse or many other good things. It doesn’t matter so much if there’s some egg white in the yolks, but if there’s more than the tiniest smidge of yolk in your egg whites, they won’t beat up into stiff peaks.
It’s not easy to separate eggs; it takes practice. The best thing is to practice when you’re making something where the eggs don’t really have to be separated, like scrambled eggs.
There are several different ways to separate eggs. One way is to crack the egg into your hand and let the white (the transparent part) dribble through your fingers into a bowl. Then put the yellow yolk in another bowl. This is pretty easy but it gets your fingers sticky.
Another way to separate eggs is to carefully crack the eggshell in half so that it makes two little cups. You should try to get the two cups to be about the same size, each half of the eggshell. Gently pour the yolk from one half to the other half, letting some of the white drip out as you go. Then pour the yolk the other way, letting more of the white drip out. You can usually pour the yolk three or four times before it begins to break, and then you have to stop and put the yolk in the yolk bowl.
Until you’re very good at separating eggs, you should do them one egg at a time, and only put the eggs together after they are successfully separated. That way if you mess one up, you haven’t messed all of them up. If you do mess one up, you can sometimes scoop out a little yolk with a teaspoon or with the eggshell. But if it’s more than just a tiny bit of yolk, it’s better to throw away the egg and start over with another one.