Experience

Experience is knowledge of and skill in something gained through being involved in it or exposed to it over a period of time. It generally refers to know-how or procedural knowledge, rather than propositional knowledge. Knowledge based on experience is also known as empirical knowledge or a posteriori knowledge. A person with considerable experience in a certain field is called an expert.

If someone is recounting an event they witnessed or took part off they are said to have had a "First hand experience".

Experience points is a number used in almost all Role Playing Games to formulate how long ones character has progressed in the game. It is usually abbrevated to "exp" or "xp" in such games.

See qualia