Most recipes are based on large size eggs. Open the box and look at the eggs. The shells should be clean and uncracked but slightly dull. Shiny shells are a sign of old eggs. Shake the egg.
Fresh eggs make no sound.
Old eggs slosh in the shell. Battery eggs are laid by chickens permanently caged. Although not labeled as such, most supermarket eggs are battery raised. Free range eggs are laid by uncaged chickens which are free to peck and scratch. These eggs have the same nutrient content as battery eggs.