1. Alternator
   Cylinder
2. Radiator
   Carburetor

Alternators produce alternating current, which is converted to direct current by auxiliary parts. Alternators became increasingly important as cars gained a lot of electrical creature comforts, like heated seats and subwoofers.

1. Crank pulley
   Fan belt
2. Timing belt
   Starter motor

Belts of various kinds have been essential to the workings of machines since the first days of engineering. The fan belt runs the cooling fan in the engine, hence the name.

1. Block
   Knob
2. Strut
   Tray

The engine block is where the magic happens! Or, at least, where the essentials of combustion occur.

1. Bearing
   Thermostat
2. Sump
   Turbine

"Turbocharging" takes its name from the use of exhaust gas to drive a turbine that forces extra compressed air (and fuel) into the cylinder for more power. A supercharger works similarly but is powered by the car's electrical system to avoid turbo lag.

1. Dipstick
   Fan belt
2. Oil pump
   Air filter

Sorry, dipstick, but while you're part of the lubrication system, you are somewhat less than essential. It's the oil pump that gets the engine's oil where it needs to be, which keeps everything running smoothly.

1. Dipstick
   Fan belt
2. Stick shift
   Spark plug

The answer. of course, is "dipstick." There's a cruder version of this insult, but we can't say it here.

1. Drafts
   Seals
2. Pistons
   Sumps

The piston travels up and down in the cylinder, moved from the force of the fuel/air combustion. Fun fact: A skull and crossed pistons is the symbol of the Outlaws Motorcycle Club. They are the traditional rivals of the Hell's Angels.

1. Crankcase
   Hub cap
2. Radiator cap
   Rocker arm

Of course, many engine parts are hot to the touch when the ignition's first shut off. But trying to take the cap off the radiator in an overheat situation is a way to give yourself a nasty steam burn.

1. Catalytic converter
   Water pump
2. CV joint
   Starter motor

Catalytic converters work by using a chemical reaction to convert harmful emissions (carbon monoxide, nitrogen oxides and hydrocarbons) to less harmful ones. It isn't just vehicles that use catalytic converters, either; they are found in fuel-burning stoves and heaters, as well.

1. Fan belt
   Radiator
2. Manifold
   Strut plate

An intake manifold supplies the fuel/air mixture to the combustion cylinders. An exhaust manifold takes the exhaust gases from the combustion process and shunts them all into one pipe.

1. Bolt
   Cylinder
2. Piston
   Pump

A cylinder, in geometry, is a three-dimensional figure defined by two circles, one at each end — or you could just visualize a can. In the engine, it's where the fuel-air mixture is compressed and ignited, moving the pistons to generate motion.

1. The coil
   The head gasket
2. The camshaft
   The dipstick

In general, a gasket is a seal. A head gasket keeps the cylinder from losing compression, which would make the engine lose power.

1. Crankshaft
   Coil
2. Multi-accessory belt
   Timing belt

A chief engineering problem in making the earliest cars, trucks, etc, was getting power, or motion, to "change direction," so to speak, from the up-and-down motion of the pistons to the rotational motion needed to move the wheels. The crankshaft is an important part of that, transferring the energy generated by the combustion process — or its initial motion — to the powertrain.

1. Cylinder head
   Distributor
2. Multi-accessory belt
   Dipstick

The name is apt — it distributes electricity. The reason the distributor has to do this in a particular order is that the cylinders must fire in a certain side-to-side order for balance. Otherwise, the engine would rock violently enough to shake the car.

1. Oil filter
   Oil pan
2. Dipstick
   Crankcase

Of course, it's the oil filter. You don't want your new oil contaminated with the old oil's dirt. Keeping the engine oil free of gunk is critical to keeping the engine running well for years.

1. Camshaft
   Fan belt
2. Pistons
   Starter motor

The camshaft rotates pear-shaped plates, whose intermittent pressure causes the valves to open and close. This part of the engine is the source of all those commercials gloating over an engine's "double overhead cam."

1. Cylinder head
   Carburetor
2. Radiator
   Transaxle

This is a change from older flathead engines. In those, the valves were in the cylinder block.

1. Camshaft
   Fan
2. Serpentine belt
   Solenoid

The fan, one of the simplest human inventions for keeping cool, is still essential to the functioning of modern cars.

1. Crankshaft
   CV joint
2. Rocker arm
   Transaxle

Unsurprisingly, the rocker arm is named for its characteristic motion, which takes the circular motion of the cam lobe into the linear movement needed to open the poppet valve. We would have liked for it to have been invented by Alice Cooper on his day off, but sadly, that's not the case.

1. Air intake manifold
   Ignition coil
2. Mulitaccessory belt
   Starter motor

Your car battery doesn't actually have much more voltage than the one you'd put in a smoke alarm. The ignition coil, or spark coil, increases the voltage until it's capable of firing the spark plugs, which is essential to the combustion process.

1. A bearing
   A flywheel
2. A poppet valve
   A fuel filter

A "poppet valve" was sometimes called a "puppet valve." Both terms come from the idea of the valve being controlled from above and making an up-and-down motion, like a puppet. It's also sometimes called a "mushroom valve" because of its shape.

1. Clutch
   CV joint
2. Fuse box
   Solenoid

In the movie, "Road to Perdition," a boy is asked what the clutch does, and says, "it clutches." Well, not exactly. The clutch is several discs that connect and disconnect shafts, meaning it is the key connection between the engine and drive train. When you take your foot off the clutch pedal, you are actually "letting out" the clutch, not engaging it. Many people get this backward.

1. Alternator
   Rocker arm
2. Starter motor
   Timing belt

The starter motor is what comes to life when you crank the ignition. It powers the first two strokes of the engine's four-stroke cycle, after which the process becomes self-perpetuating.

1. Battery
   Distributor
2. Cylinder head
   Carburetor

A car's battery looks sizable and impressive, but it often has only 12.6 volts and is used primarily to provide the energy to start the engine. The rest of the electricity that makes the engine work and provides all those enjoyable extras — like the radio — are generated from the engine and the alternator.

1. Cylinder seal
   Fan
2. Propelling nozzle
   Rocker valve

A propelling nozzle is a part of a gas turbine which helps to maximize the velocity of the propelling gases exiting the engine. These are used in jet engines, which have turbofan engines.

1. Battery
   Hotwires
2. Magneto
   Timing belt

Magnetos aren't entirely gone; some airplanes still use them because they can help provide redundancy and enhanced combustion. (It's also possible that engineers liked the cool, atomic-age name so much they couldn't let them go completely obsolete).

1. Bushing
   Ball bearing
2. CV joint
   Wrist pin

The wrist pin doesn't just connect the piston and connecting rod. It also allows greater flexibility, letting the rod adapt to the motion of the piston without breaking.

1. Bushing
   Glow plug
2. Rocker
   Solenoid

The solenoid is an electromagnet that, when you turn the key, closes a pair of contacts that allows current to flow through the starter motor and gets the ignition process started. You might remember the solenoid from its use in the 2005 "War of the Worlds" remake. Tom Cruise's mechanically inclined character suggests that replacing the solenoid in a car will correct the ignition failure caused by an electromagnetic pulse.

1. Crankcase
   Cylinder head
2. CV joint
   Crank housing

This is a protective housing for the crankshaft and its connecting rods. It's also oddly fun to say aloud.

1. Coolant reservoir
   Fan belt
2. Fuse box
   Thermostat

The thermostat is located between the engine and the radiator and, once the engine gets hot enough, opens to allow coolant to flow and maintain a proper temperature. It's a simple but essential piece of technology for your vehicle.

1. Camshaft
   Flywheel
2. Clutch
   Bushings

The full definition of a flywheel is a bit complex, but suffice to say it stores and smooths out the flow of the intermittent energy produced by the constantly moving pistons.

1. Alternator
   Distributor
2. Multi-accessory belt
   Timing belt

A multi-accessory belt, as the name implies, replaced a system that used several belts to run various engine parts like the water pump and the alternator. It's more efficient than multiple belt systems, but the downside is that, if this belt breaks, a lot goes wrong all at once.

1. Crankshaft
   Head gasket
2. Piston
   Spark plug

Many veteran mechanics have a story about breaking off a spark plug in the block. The best ones will also tell you the first step in dealing with it: Go have a cup of coffee or take a walk until you're not upset any more and can approach the problem with a cool head and a lot of penetrating oil.

1. Crankshaft
   Camshaft
2. Dipstick
   Tappet

Strictly speaking, only overhead cam engines contain a part that could be called a tappet. In fact, a tappet is a fairly general term, meaning "an outcropping part that causes linear motion," However, it's associated enough with engines that car experts Tom and Ray Magliozzi called themselves, "Click and Clack, the Tappet Brothers" on their "Car Talk" radio program.

1. Distributor cap
   Crankcase
2. Ignition wires
   Starter motor

The advent of distributor-less ignition might have been progress in terms of engine design. However, it ruined a good theft-protection and drunk-driving prevention strategy — stealing the distributor cap. Since it was easy to remove, and the car would go nowhere without it, it was a quick way to disable the vehicle.