Lets look at the Engine oil first.
Engine Oil After you had an oil change, a few drops here and there are ok, and do not forget an older engine with older seals may constantly leak a little. If that is the case, you might want to get it checked, have some bolts re tightened or seals replaced at the oil pan and on top around the valve cover. The oil filter might get a little loose or the bolts at the oil pan are loose too, causing it to leak. In this case, just check all the bolts, and turn the oil filter a little bit more. Easy steps to do and cheap!
Antifreeze / Engine Coolant Coolant can be either green, yellow or blue depending on the vehicle manufacturer. Most vehicles have a radiator located just behind the grill. Not enough antifreeze / coolant will cause the engine to overheat. There is usually an "overflow or fill" tank where you can add antifreeze / coolant to your cooling system. If need be add some more fluid to the overflow reservoir, not to the radiator directly, and WARNING; never open any of those caps when the engine is hot … it will splash out like a spewing volcano leaving you with some nasty burns.
Clear Water Most vehicles today are equipped with air conditioning, and what you see dripping even after the engine is shut down, is nothing more than condensation from the air conditioning system. On most vehicles you see this in front of the passenger side on your car, where the air conditioning system is located.
Brake Fluid Brake fluid is clear and oily to the touch with a sweet smell on your hand. The first thing to look at is the cover at the brake cylinder. Many times when you check the fluid in a hurry and do not shut the cap properly, it will leak out. Whenever you depress the brake pedal, you inflict a lot of pressure into the system and there are many points where it could leak. If you have a leak somewhere along the line, it will have to be replaced. If you see something on the inside of the tire that looks like water, most probably, it is break fluid leaking from a caliper on the wheel. That too, needs to be replaced. While leakage of the brake system is rare, you'll probably feel a 'soft or spongy' brake pedal feel when depressing the brakes, which can lead to brake failure. A stop to the mechanic is no option. A faulty break system can be deadly!
Transmission Fluid This fluid is typically red, when old or overheated, brownish or when contaminated or diluted with foreign liquids it will turn to a 'milky-pink' color. Some transmission fluids of certain vehicles may be clear or amber in color. If you have a front-wheel-drive vehicle, then your transmission is next to the side of your engine underneath the hood. If you have a rear-wheel-drive vehicle, then your transmission is located in the center of your vehicle just under the dash under that 'hump' in the center. Should you have a leak, to refill you need to take the dip stick out, and pour it trough a funnel into the dip stick line.
Power Steering Fluid Some vehicle manufacturers may use a fluid that is almost clear or yellowish / amber. The power steering reservoir is typically mounted at the power steering pump which driven by a belt on the engine. Leaks generally occurs within the power steering lines and sometimes also at the "rack". In that case it will have to be replaced.
Windshield Washer Fluid Pink or blue fluid, sometimes a little foaming, would indicate that your windshield washer reservoir is leaking. For the front windshield, this reservoir is under the hood in the engine compartment. For vehicles with rear wipers, it's usually mounted behind a panel in the rear left or right side of SUV's and Vans.
Gasoline Gasoline is a clear fluid with a strong smell and is highly flammable. Stored in the gas tank usually located at the rear of your vehicle. The tank is made out of metal or depending on vehicle manufacturers, heavy plastic. Leaks are mostly detected by a gasoline smell in the cabin. Fuel lines can burst or rupture. Connection points are another point of leakage, rarely however. If there is continued fuel odor in the car, it should be checked out as soon as possible. A broken line in the engine compartment that is spewing fuel on to the hot engine could spell a disaster.
Diesel Fuel Diesel fuel looks like light oil. While not as flammable as gasoline, it can ignite in the right conditions. Just as with gasoline, a leak should be taken care of as soon as possible.
Gear Oil Gear oil is a light tan or black and is considered 'heavy' or thick oil. Leaks can occur in you manual transmissions, differential (rear-end on rear-wheel-drive vehicles) or axle. Since gear oil is used widely among certain components, a gear oil leak may be present at a number of locations underneath a vehicle. Any leaks should be taken care of early; the longer you wait, the more expensive the repairs are going to be.
Battery Acid Is a clear fluid that contains sulfuric acid and will smell like rotten eggs. When dry, it will show an almost salty white appearance. For a leaky battery, there is only one cure; replace immediately! Battery acid is corrosive and may damage your paint and any contact with skin is harmful. Wash your hands with water as soon as possible, do not touch no facial parts with your fingers while dirty!
Shock and Strut Fluid Shock and strut fluid is typically a heavy dark brown oil. Evidence of leakage is by an external stains on the shock or strut housing. On struts and shocks there is nothing to repair or refill, they must be replaced preferably in pairs, mostly starting with the front pair first.
By taking care of drippings from your car, you may ensure a longer life of your car and preserve your nerves for other events of which you might not have control over!