An experiment is a planned operation carried out under controlled conditions or in a way that can be repeated.

An outcome (or simple event) is the exact result of an experiment usually written down to form the statistical data.

a certain set of outcomes under considerations. Usually denoted with a capital letter,[br]like E.

The probability of event E occurring is written P(E). [br]P(E) = 1, if we are certain that the event will occur. [br]P(E) = 0, if event E cannot happen.[br]P(E)= 0.5 =50% if event E is equally likely to occur or not occur.

[color=#ff0000][u]The collection of all possible outcomes of the experiment.[/u][/color] Often denoted by the Greek capital letter omega, Ω. Our textbook uses capital S.