Our cars are complex machines that have many different moving parts constantly working together to get you wherever you need to go. It can be difficult to keep up with the different issues that can pop up without any notice. Furthermore, sometimes it can be difficult to even identify what the problem is.
Your car is made up of a lot of different metal pieces, so paying attention to the location of the sounds the metal can make is crucial. If you hear a clinking sound in or around your tires, pay attention. You could have a loose lug nut inside a hub cap. This needs immediate attention, and if you suspect this is an issue, take your car to your mechanic as quickly as possible.
Your brakes are made up of several fail safes and warning signs in order to give you ample warning to get them changed when needed. If you hear a high pitched squeaking or squealing when you apply the brakes, it means your brake pads have worn down. That sound is coming from a sensor made specifically to let you know that your pads are on their last leg so that you can have them replaced before damage is done to your brake system.
High pitched squealing coming from under you hood is probably belt going bad or that is knocked out of place. Typically, you can see these belts, which are about an inch wide, black rubber making a complete circle around a pulley system under your hood. If one looks frayed or stretched thin, get to a mechanic immediately to get it replaced. Different belts control different aspect so your vehicle including your power steering, so being on the road when one of these goes completely out could make for a dangerous situation.
If you feel and hear a deep grinding when you apply your brakes, this means your brake pads are completely worn and your rotors are now making contact to caliper. This is more or less your last warning to get your brake pads and now rotors replaced before serious damage is done. Your brakes are an important part of your vehicle, and neglect of them can lead to serious injury or even death to yourself or someone.
A high pitched hissing sound coming from the front of your vehicle can suggest an overheating problem, a vacuum leak, or a whole array of other issues. If you there is a leak somewhere in your engine, this hissing sound could be the result of liquid chemicals making contact with hot exhaust or other engine parts. This could be a serious hazard, and you should never attempt to touch parts of a hot engine, especially if you are unfamiliar with the different working parts.
Because we depend so much on our vehicles and because they are intricately working pieces of machinery, if you notice something is out of the ordinary, the best thing to do is to take it to a mechanic. Describe what you are experiencing, and let them assess the situation. Instead of just guessing or hoping for the best, let your trusted mechanic do what they do best!