# Probability Theory

## What is Probability Theory?

Probability theory is a branch of mathematics that deals with the study of random events and the likelihood of their occurrence. It is used to describe and analyze the outcomes of experiments or observations that involve some element of uncertainty.

In probability theory, an event is a possible outcome of an experiment or observation. The probability of an event is a measure of the likelihood of that event occurring and is expressed as a number between 0 and 1, with 0 representing an impossible event and 1 representing a certain event.

Probability theory is based on the idea of a sample space, which is the set of all possible outcomes of an experiment. The probability of an event occurring is then determined by the number of ways in which the event can occur, divided by the total number of possible outcomes in the sample space.

Probability theory is used in many fields, including science, engineering, economics, and psychology, to analyze and predict the outcomes of experiments or observations that involve some element of uncertainty. It is also an important tool in statistical analysis, where it is used to make inferences about a population based on a sample of data.