# 2.1 Basic Probability Concepts

*Random experiment* is an experiment with its outcome being unknown ahead of time but all of its possible individual outcomes being known [1]. The set of all possible outcomes of a random experiment constitutes its *sample space*, denoted by *Ω*. Each individual outcome in the sample space is referred to as a *sample point*.

A subset of a sample space associated with a random experiment is defined as an *event* that occurs if the experiment is performed and the outcome observed is in the subset defining the event. There are two special events: a *certain event* (sample space itself *Ω*) that occurs with probability ONE (1) and an *impossible event* (empty set ∅) that occurs with probability ZERO (0). Because events are sets, the operations in the set theory like complement, union, and intersection can be applied to generate new events.

If two events *A* and *B* do not share any common sample points, i.e. *A* ∩ *B* = ∅*,* then *A* and *B...*