There are three types of lies: Omission, where someone holds out on the facts; commission, where someone states facts that are untrue; and paltering, where someone uses true facts to mislead you. It isn't always easy to detect, but there are a few telltale signs.

Polygraph machines, better known as lie detectors, are crap. They can't tell whether you're lying, just whether your body is doing some of the things that bodies do when we're nervous: Sweating, for example. But there are a few tricks that, according to rumour, can let you mess with the results.

In the past, we've shown you how to be an effective liar. But it's important to not fall into the traps of others - especially those that lie to us most often. Here's how to tell when a CEO or a politician's making false promises.

Misusing statistics is one of the most powerful ways to lie. Normally, we teach you how to avoid misinterpreting statistics, but knowing how numbers are manipulated can help you spot when it happens. To that end, we're going to show you how to make data say whatever the hell you want to back up any wrong idea you have.

Polygraph tests often aren't admissible in court because they can't actually detect lies, but instead physical indications that often accompany them. Your intentions aside, it's good to know how to beat the polygraph to ensure it doesn't mistake anxiety for untruths.

In this episode we're talking about bullshit: What it is, how to detect it, and how to call it out. First, staff writer Nick Douglas joins us for a rousing game of "Two Truths and a Lie". Then we talk to Carl Bergstrom and Jevin West, professors at the University of Washington who teach a course called Calling Bullshit. Finally, Alice talks about why we're so susceptible to bullshit with staff writer Beth Skwarecki, who writes the Bullshit Resistance School column right here on Lifehacker.

There's an old adage that when you repeat a lie enough, it becomes the truth. Psychologists call the illusory truth effect. BBC Future digs into how it works, why it works and why it doesn't.

The first evil skill I acquired was subterfuge. Trying to deceive my parents is one of my earliest memories. I escaped from my crib by removing one of its loose bars and then, after climbing out, put the bar back in -- as if to trick my parents that I was still in there.

Getting rid of your tells is hard to do, assuming you even know what they are. If you want to be a better liar, however, you can create a fake tell so others can't figure out when you're actually lying.

It's not always easy to be honest with people. We're all guilty of telling a white lie or pretending to be okay with something that secretly drives us nuts. If you have a hard time being brutally honest with someone, think of it as a chance to improve your relationship with that person.

The word "no" is used a lot by liars trying to cover up their tracks. According to a former FBI counterintelligence agent, the way someone says it can truly reveal their deceptive behaviour.

Whether you're trying to finagle the truth from a teenager, or you suspect a friend is fabricating a story, catching someone in a lie takes a bit of effort. Scientific American took a look at military interrogation tactics to see what works in everyday life and found asking left-field questions is a good way to trip up a liar.

Not every lie is bad. Some lies keep people happy and keep our relationships strong. Whether you're keeping a close friend's secret or telling our mother we love the sweater she knitted us, some lies are necessary -- even helpful. Before you lie, though, ask yourself a few questions to see if a lie is really worth telling.

Catching a liar in person usually means looking for a variety of nonverbal cues, but that's not as easy when it's written in a text message or email. For that, The Wall Street Journal suggests looking for subtle changes in how someone words things.

All kids lie at some point, and we can't always tell when they're doing it (those little buggers). There are two things, however, you can say to your children to get them to be honest.

You can never prove someone is lying just by looking at non-verbal cues -- but they can let you know when something might be off. David DeSteno, a professor of psychology at Northeastern University, conducted a thorough study and found four non-verbal indicators you might want to look for.

Don't click play on this video yet or you'll ruin the surprise! First, try this quick test to find out if you're an expert at deception or not.

We all know that our willpower can be drained as the day progresses, but it turns out that as we become more tired, we lose all kinds of faculties. Scientific American points out that time time of day can an effect on whether or not we tell the truth.

When someone is lying about something, they're usually unconsciously trying to distance themselves from the situation to make the lie more tolerable to tell. As The Wall Street Journal points out, this means that when people lie they tend to use the word "I" a lot less.