Michael Phelps may have conquered the 2008 Olympics, but he might also be destroying students’ computers.

Typing his name in five major search engines carries a 40 percent maximum risk of infection, according to a recent report by the security technology company McAfee. Hypothetically, 100 out of the 250 websites that appear after a search of “Michael Phelps” would be infected.

Common infections from dangerous search terms include Trojans and malware — short for “malicious software.”

“You can expect that someone is going to get into your computer” when searching for “free music,” said Stanley Ziewacz, a graduate student in computer science.

That search phrase combines two risky terms, in fact. Any search that includes the word “free” is likely to be an infected website. And the top three riskiest terms in the United States were “word unscrambler,” “lyrics,” and “myspace” — all with a maximum risk of 50 percent.

Experts say there are several reasons for the phenomenon.

It’s difficult for infected sites to be completely weeded out from searches because new scams constantly replace old ones, the report said. Furthermore, the sites pop up because search engines will return bad websites as their top results, said E.J. Jung, a UI assistant professor of computer science.

The safest search terms were those related to the economy, such as “financial crisis,” “unemployment,” and “Wall Street.” That’s because companies tend to keep close tabs on their names and websites.

“Larger corporate websites are pretty well maintained; people keep an eye on them,” said Jane Drews, a UI information technology security officer. “We typically see problems with smaller websites, personal websites, or noncommercial websites.”

Fortunately the UI offers all students a protection software for free. It has three different components to it, Drews said — anti-virus and spyware, proactive threat protection, and network threat protection.

And choosing what websites to enter may be more of a gamble now than before. Hackers’ motives have changed over the years, Ziewacz said.

“Now it’s for profit and not for fun,” he said.

And computer experts agree it is ultimately the user’s responsibility to decide which websites to enter.

“What I always tell my students is to be very careful about what they allow into their system,” Ziewacz said. “Imagine [hackers as] people walking among the rooms of a hotel just trying every door, and if a door unlocks, they’ll go into the room.”