For young travelers backpacking throughout the world, often the cheapest place to stay is in a Youth Hostel. A hostel is kind of like a hotel, except it's filled with other young backpackers, you share rooms and sleep in uncomfortable bunk beds, and they can offer you a range of activities to choose from and stay active. Typically, the age range to stay in a hostel is between 18-25, though some have exceptions. Though I've done a lot of traveling, my main area of expertise comes in the hostels of Europe, so that's what I'll focus on here.

There are a lot of things to take into account when trying to find a good hostel. Two of the best Web sites you can use to book them in advance are Hostelbookers and Hostelworld. Both sites are great because you can search from almost any country in the world and get user reviews on the hostels. Of these two, I would say that Hostelbookers is the best and easiest to use. This site also narrows down the most popular destination and hostels so you can find places easier. There are tons of user reviews with pictures and feedback. The best thing about this site--no fees for using it.

You can also look into guide books for hostels if you don't want to book before you go. Sometimes it's good to check out a couple places before settling. If you think the first place you see is nice, check out another, because the second place might be awesome. Good guide books to check are Let's Go, Frommer's, and Lonely Planet. Before you go, you should know about some of the Pro's and Con's of staying in a hostel.

Pro's
-A hostel will save you a lot of money, especially in the larger cities of Europe where the euro is very strong. Staying in a hotel in Paris for a few nights could empty your wallet, and though it might be romantic to stay in a posh location in the City of Lights, you should save that for when you're older and can afford it.
-It will give you a chance to meet some really cool people. This is especially great if you're traveling alone. It's a real refresher to make some friends when you're all by yourself, and though they are "single-serving" friends, you are the same thing to them, and your relationship is built off of that need to mingle with someone. It also gives you a chance to network with people. If you meet someone in a hostel in Dublin who's from Los Angeles, maybe the next time you go to LA you can stay with them. Here's a true story. I met a guy in a bar in Dublin in February who was staying at a hostel down the street from mine. He was studying in Berlin and I was in Sevilla. I saw him in a dance club in Prague in March. In late May he was staying in my hostel in Madrid. It just goes to show you can meet people all over Europe.
-Many hostels have activities and let you know about special deals in the city. At The Flying Pig Downtown Hostel in Amsterdam you can find tons of fliers for free walking tours and bike rental shops. The hostel also has an awesome bar/lounge scene where you can just chill and relax. The music plays all night and it's livelier than some of the bars outside. Only hostel guests can get in. At Balmer's Herberge in Interlaken, Switzerland, you can get deals on canyoning and skydiving for staying there. Balmer's also has the only bar in the town. Other places will also organize games, karaoke, or pub crawls with someone who knows the city.
-The location of the hostel is key. This is a tough one, though. Some hostels can be smack dab in the middle of the action, or at the very least next to a metro stop. This is because they can often be smaller than hotels and take up less space where rent will be higher. However, you could also arrive to your hostel and find that it's in the middle of no where, leaving you few options and long distances to cover. I stayed at the Three Ducks Hostel in Paris. It was one of the cheapest hostels and had a bar, but it was in the 15th arrondisement, a neighborhood that isn't known for much of anything. The metro ride to get anywhere good was at least 15 minutes.

Con's
-The place could very well be a dump. They might entice you will a low price and free internet, but you could be stuck in a 32-bed room with lousy roommates who keep you up all night, and no lockers. You could be in the middle of no where and have no one to hang out with. I stayed at one of the only hostels in Lucern, Switzerland, and I had to walk 25 minutes just to get to the center of town. It was actually located in a neighborhood, and almost no one else stayed in the hostel. I was traveling alone and had nothing to do for two days.
-You could have that sketchy guy in your room. If you've traveled in hostels before, you know it's bound to happen at some point. I've got my share of horror stories which I won't get into now, but you need to be ready to accept that a weird old naked man could be staying in your room or that your top bunk buddy scratches his balls all night. These things happen.
-You could find that the showers have no pressure, the toilets aren't fit for a farm animal, and your bed has bugs. It's best to just push through it and keep saying mind over matter, but sometimes it's downright awful.
-Some hostels will have curfews and if you're not back in time it's too bad, because you'll be spending the night on a park bench. You can yell all you want about paying for a bed, but they won't care. If they have rules, you have to follow them.

These are just a few of the things to keep in mind when you are thinking about staying in a hostel. It's important to remember that it could all depend on who you're traveling with and your participation in the city, which can sometimes change how you look at an event. You can have a great experience or come back with a cautionary tale. It's all up in the air, but that's also part of the fun.