To cook by gently simmering in liquid that is just below the boiling point (180 to 190 degrees) is called poaching. This is the temperature at which the water starts to move. Julia Child calls this stage a "shiver"; James Beard referred to it as "feeble ebullition." This is also the temperature at which food is blanched. Many foods can be poached - fish, chicken, eggs….
Poaching an egg is the best way to learn how to poach. The fresher the egg the better and it’s best to start with one that’s chilled. The water has to be at a stage that is not boiling with full bubbles but hot enough to cook the egg quickly.
Crack the egg into a teacup and then pour the egg from the cup into the poaching water. (This is so if you break the yolk the egg won't be wasted.) Let the egg cook slowly, watching so that the water never comes to a full boil. Use a slotted spoon to remove the egg from the water.