Valve Type
Standard (also called Schrader) valves are the most common valve type for bicycles. This short, sturdy valve is also used on car tires and other inflatables.
Presta valves are typically found on performance road and mountain bikes. They have built-in valve locks which you twist to open before inflating.
An easy way to remember is: 'S' is for Standard (Schrader, Short, Sturdy) and 'P' is for Presta (Performance, Premium).
All inflatable tubes are subject to deflation from mis-installation and certain hazards.