Final answer:
A character or group of characters that defines and stores data is called a variable, which is used in computing to hold and manipulate information and can represent different kinds of numeric or categorical data.
Step-by-step explanation:
The term you are looking for that represents a character or group of characters which defines and stores data is variable. In computing and data processing, a variable is used to store information that can be retrieved and manipulated by a program. Often represented by an identifier (a name), variables can hold different data types, including numbers, characters, and strings, and their values can change throughout the execution of a program.
For example, the variable X might represent the number of visitors to a website, while the variable Y could represent the visitors' average time spent on the site. These variables can then be used in computations, such as calculating the total number of minutes spent on the site by all visitors. It's important to note that in statistics, variables can also represent characteristics such as weight or favorite subjects (numerical variables) or categories like political affiliation (categorical variables).