Oil levels refer to the amount of oil present in a vehicle's engine. Maintaining the correct oil level is crucial for proper engine function, as oil lubricates moving parts, reduces friction, and helps prevent overheating. Regularly checking the oil level can help identify leaks or the need for an oil change. To check oil levels, use the dipstick, a metal rod located in the engine compartment. After pulling it out and wiping it clean, reinsert it and remove it again to see the oil level. The dipstick usually has markings indicating the minimum and maximum levels, ensuring that the engine has enough oil for optimal performance.