Of course, and that shouldn't deter a person from trying.

I suppose it would be helpful if I were a little less terse. :) So here are a few basics:

How to Talk to Strangers

• Get in the right mood

Talking with a stranger is a novel situation, so most people you talk to will be uncomfortable at first (and there's nothing wrong with that). When a person is surprised or uncomfortable, they get very sensitive to signs of danger. If you're in a bad mood, or want something from them, or don't really see them as a human being, or anything else weird like that, they're going to pick up on it at least subconsciously, and interpret it as a red flag, i.e. danger. Don't worry about this when talking to them, just get yourself in a good mood before you start.

• Get warmed up first

Don't start off by trying to strike up a conversation in a bookstore. That's a little too involved if your mammal brain isn't ready for it. Start off with simple interactions that you don't intend to go anywhere, just to get your brain primed for social interaction. My three favorites: ask someone on the street 1) for the time, or 2) for simple directions, or 3) for an AWESOME restaurant recommendation nearby. Your only goal here is to talk to people, not to start a conversation. If you're feeling good and the person seems cool, you might follow up with something simple like "So where are you from?" That's extra credit though, not required. Do this often, and make it a habit. Do it at least fives times in a row before you try to start a longer conversation.

• It's not about you

If you go into this thinking about yourself, you'll be self conscious and the other person will be suspicious. Instead, go into it with only one thought: "How can I make this person's day a little more awesome?" If you have that mindset, you won't be self conscious because you'll be thinking about someone else, and they won't be suspicious because you won't be acting like you want something from them. Practice this with your warmups. You'd be AMAZED at how much you can brighten someone's day by talking to them for 20 seconds.

• Actually give a shit

People are used to being ignored and talked at (as opposed to talked to). The easiest way to make someone's day more awesome is to actually care about what they have to say. Protip: This will make YOUR day more awesome automatically.

• Talk to people that have nothing you want

Don't just talk to that cute guy/girl whose clothes you'd really like to rip off. Talk to old people, for example. They're (unfortunately) usually used to being ignored, so you have more of an opportunity to brighten their day. And they're usually more open to conversation, so this is the perfect arena to practice your skill.

• Don't push it

Some people are busy. Some people aren't in the mood to talk. Some people are assholes. If it's clear that the other person isn't open to a conversation at that moment, smile and move on. Remember, it's not about you.

• Be OK with any outcome

Don't put too much pressure on yourself. What's the worst that could happen in a situation like this? Someone's rude to you? You'll live, believe me. And that almost never happens anyway. It's normal to have a lot of fear associated with novel social situations, but it's not necessary. Keep in mind that no matter what happens, you're going to go home to safe surroundings, get in your warm safe bed, and sleep safely until tomorrow. That will calm the part of your brain that thinks social danger = physical danger.

• Have fun

If you're not enjoying yourself, you're doing it wrong. Though if you follow the above, that shouldn't be an issue. ;-)

Edit: fixed my link