If you have oil or any other kind of fat in your bowl, the peaks may not form. You need a completely clean bowl.
Any bowl or utensil that is used when beating egg whites has to be perfectly clean and grease-free. When air is beaten into egg whites, the proteins of the egg white open up, which makes the whites form a semi-solid. If there are any lipids introduced into the egg whites they prevent the whites from forming a semi-solid state by surrounding the proteins of the egg whites and preventing the proteins from opening.
Beat the egg whites with your mixer on high speed until the beaten whites form stiff peaks.
beaten egg whites are
baking powder.
When you whisk the egg whites, It incorporates air into it. So when it foams, that means that there is simply air in it.
whipped eggs on toast
Egg whites are the clear liquid within an egg. Think of the contents of an egg being of two different substances....the yolk (yellow part) and egg whites (the clear parts).
meringue, like a lemon meringue pie
Beaten egg whites, sugar: http://whatscookingamerica.net/Eggs/perfectmeringue.htm
Yes, egg whites can be over-beaten. They can get too dry and difficult to fold into other foods. Or the foam might even break down.
What is a mixture of egg whites and sugar beaten into stiff peaks
The exact term is 'stiff but not dry' the idea is to make it stiff enough to hold itself whilst being added to whatever you're adding it into.