(CNN)Just because it's on the internet doesn't make it true. It seems so simple, but if everyone knew that, Facebook and Google wouldn't have to pull bogus news sites from their advertising algorithms and people wouldn't breathlessly share stories that claim Donald Trump is a secret lizard person or Hillary Clinton is an android in a pantsuit.
1. Fake news
These are the easiest to debunk and often come from known sham sites that are designed to look like real news outlets. They may include misleading photographs and headlines that, at first read, sound like they could be real.
2. Misleading news
These are the hardest to debunk, because they often contain a kernel of truth: A fact, event or quote that has been taken out of context. Look for sensational headlines that aren't supported by the information in the article.
3. Highly partisan news
A type of misleading news, this may be an interpretation of a real news event where the facts are manipulated to fit an agenda.
The shocking or teasing headlines of these stories trick you into clicking for more information -- which may or may not live up to what was promised.
This one is tough, because satire doesn't pretend to be real and serves a purpose as commentary or entertainment. But if people are not familiar with a satire site, they can share the news as if it is legitimate.
Alexios Mantzarlis trains fact-checkers for a living. He says it's important to have a "healthy amount of skepticism" and to think, really think, before sharing a piece of news.
"If we were a little slower to share and re-tweet content purely based on the headline, we'd go a good way towards combating flasehoods," he told CNN.
Melissa Zimdars points out that even those who spend a lot of time online aren't immune to fake content.
"People think this [thinking] applies only for older people," she told CNN. "I think even early education should be teaching about communication, media and the internet. Growing up with the internet doesn't necessarily mean you're internet savvy."