Body language seems like a foreign language sometimes.
You've probably been told a few tips, like that you shouldn't look up and to the right when attempting to lie because it divulges that you're attempting to think up a story.
However, if you ask the average person on the street they probably can't tell when interest is being registered.
It seems YouTube is here to help.
A recent YouTube video by TheWacky discusses how we can interpret body language to interpret a person's thinking, or their personality traits.
For example, the video states that brushing away hair could be done by women to draw attention to feminine features of their face (or they could be brushing their hair), while men blinking frequently is a sign that they're nervous (or they have something in their eye).
Meanwhile, eye contact can be a signal of confidence, interest and honesty.
Licking your lips can be a sign that you are attempting to calm yourself down (they could be dry).
When you lie, you receive a rush of adrenaline - and that can cause veins in the nose to itch. If they're scratching they might by fibbing.
Lowering your head or looking at the ground could indicate you're looking for support.
In addition, people tend to take social stances, angling themselves to face their person of interest - so take a look around and see who's facing you.
You can see more body language home truths in the video below (Warning: they use some interesting language):