Asocial: Someone who lives outside the norms and rules of society. 
Antisocial: A grave psychological disorder found among psychopaths. 
Unsociable: Someone who has no or very little interest in socializing with others.

Definition: "Contrary to what most people think, an introvert is not simply a person who is shy. In fact, being shy has little to do with being an introvert! Shyness has an element of apprehension, nervousness and anxiety, and while an introvert may also be shy, introversion itself is not shyness. Basically, an introvert is a person who is energized by being alone and whose energy is drained by being around other people.

When introverts want to be alone, it is not, by itself, a sign of depression. It means that they either need to regain their energy from being around people or that they simply want the time to be with their own thoughts. Being with people, even people they like and are comfortable with, can prevent them from their desire to be quietly introspective.

Being introspective, though, does not mean that an introvert never has conversations. However, those conversations are generally about ideas and concepts, not about what they consider the trivial matters of social small talk.

Introverts make up about 60% of the gifted population but only about 25-40% of the general population."

Some things that characterizes an introvert:

- Do rather than talking
- Switches between a public and private personality
- High observation ability, usually gets the socials norms well and knows how to act as an expected role 
- Perceived as difficult to understand
- Quite restrictive in reveal things about oneself
- Usually becomes the party in a conversation that mostly listens
- Doesn't necessarily feel the need to fill up the silence in a conversation
- Prefer few but deep friendships
- Become uncomfortable with being the center
- Become exhausted of new acquaintanceship and social events
- Doesn’t identifies oneself strong in groups, often has independent views
- Doesn’t get bored easily, but finds joy in small things
- Can go long periods without intense contact with others
- Has needs of solitariness
- Sometimes perceived as stable and insensitive , but most likely with alot of feelings underneath
- Doesn’t live out all the emotions in facial expressions
- Restrained body language
- Conservative look with dull colors.

Clothes and appearance is usually not composed to attract other people’s eyes.

- Generally finds trendy and popular things uninteresting
- When feeling unhappy, doesn’t project the emotions on others and prefer to communicate less with the surrounding
- Sensitive to stimuli , easy to experience stress and distraction
- Attentive to details and quality
- Analytical and thorough in decisions. Doesn't likes quick decisions.
- Skilled at visualizing, think in pictures and have a vivid imagination
- Tend to get obsessed with a task
- Prefer to work alone to be effective
- Not a big risk-taker as an extrovert
- Minimize phonetime. Short calls and take place only for specific purpose.
- Pleasurable company is loosely connected. Prefer to do things with others but without a constant focus on dialogue.
- Comfortable with communicate through text. The channel provides space for reflection and without getting interrupted.
- The basic attitude to strangers is suspicion
- A cautious attitude to life. Not taking out profits in advance and plan with pessimistic angle.
- Rather stays silent than repeats after being interrupted
- Get inspiration and ideas from moments when caught in own thoughts
- Experience to speak infront of a large group as inconvenient and uncomfortable
- Often ponder over existential questions as: How big is the universe. 

Don't think that you can see who is an introvert or extrovert. One way to find out is when you know a person enough to know what they continuous choose to do when they want to relax.