Oil is sometimes referred to as the blood of the aircraft. It provides lubrication, cooling, and carries away waste products. Without it, or without enough of it, the aircraft engine cannot function for long. Checking the oil level is part of the preflight inspection, and knowing the proper way to add oil (use a funnel or oil spout) and how much should be required knowledge before first solo.
Knowledge of the oil system of the aircraft you fly is a must. There will be variations between models of aircraft, so if you fly many, add this information to your personal preflight briefing.
