PORTLAND, ME (NEWS CENTER -- In a world of cell phones, just about anyone can take a photo just about anytime, anywhere. A lot of those pictures are self-centered: we take photos of ourselves, our friends, what we're doing, where we are.

What is often more interesting is to chronicle what's going on outside our lives. Street photography is photography in public places, usually of people. To be a good street photographer, one must be an observer.

The idea, in part, is to capture what a great photographer called "the decisive moment."

"You just want to look for where there's energy," says Katie McGraves-Lloy. "I mean, that's the thing about a photograph, it's this flat surface so you have to figure out ways to give it energy and give it movement."

The students and instructor at the Maine College of Art begin in the classroom, discussing street photography in general, their work in particular.

"Your goal is to have the viewer look at the photograph as long as possible trying to figure it out as many times as possible."

Then the students head out the door to shoot on the streets of Portland, having been given a theme they should focus on for that evening.

Liz Bieber tells her students that if they have done well with their shooting, what they'll capture is not just an image but a story.

"They shouldn't be having to explain what's going on in the photograph. The photograph should speak all that story to the viewer."

Street photography is not for the shy. Part of what the course teaches is that there is no substitute for walking up to strangers and talking to them, even though it may be awkward.

The students have been told to see life on the streets almost like a play or theatre, to look for a range of emotions and experiences, and most important--to tell a story. As a photographer once put it: the whole point of taking pictures is so that you don't have to explain things with words.