And more and more teenagers are using them.
"I'm an addict," laughs Kate, an eight-grade student.
She along with fellow eighth-graders Emily and Jacob say they're addicted to blogging -- a place online where they can chat, laugh and vent.
"I see mine as very personal," Jacob says. "I know it isn't, and I shouldn't see it that way."
They feel so personal that they don't want their parents to read them.
"It's just a part of your life that you don't want your parents to come into," Kate says.
Most blogging sites, such as Xanga and Myspace, however, are free to use and open to any user who wants to read them.
That's why Emily's mom, Lois, did some snooping to see what her daughter was exposed to online.
"I wasn't shocked, but there was a certain level of language that I wasn't happy with," Lois said. "Some of the subject matter -- let's say, there was definitely more talk about sex than I expected."
Searching in the same way could lead a stranger to any of these students' blogs and potentially to where they live or go to school.
"A lot of information can be gained with an e-mail address or user name," says Sgt. Gary Hinnant, of the Raleigh Police Department's Cyber Crime Unit.
Hinnant says the popularity of blogs adds to his unit's caseload. While many teenagers may not give their real identities or any other identifying information about themselves, many teenagers online do.
"Kids have already been hurt in other cases across the country," Hinnant said.
That is why some schools, such as the Wake County Public School System, blocks access to blogging Web sites.
When a student tries to log on to them from a school computer, access is denied.
Parents can also monitor their teens' blog-writing with computer software, such as
, which claims to record every keystroke and entry on the computer in which it is installed.