The most common types of aviation fuel are 100LL [low lead] and Jet A.

Aviation fuel or AVGAS is color coded blue to help distinguish it from other types of fuel. Jet A is straw colored or colorless. Most reciprocating piston engines use 100LL while turbine-powered aircraft use Jet A.

Reference(s):

FAA-H-8083-25B Pilot’s Handbook of Aeronautical Knowledge pg. 7-27

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