# 4.7. GlossaryΒΆ

Booleans: A Boolean is a data type in Python that has either a value of True or False. Booleans can be used with logical operators to form complex logical questions which determine the condition for the task to be executed.

Characters: A character is a single letter, number or symbol that you can type with one key on a keyboard.

Conditional Statements: A conditional statement, also known as an if-statement, is a control structure that runs particular blocks of code only under certain conditions.

Dictionaries: Dictionaries are a data type that is comprised of key-value pairs where the keys are used to retrieve the values.

for loops: A for loop is used to iterate over a sequential collection of elements. It is used when you want to repeat the same task a certain number of times.

Fruitful Functions: Fruitful functions are functions which have a return value.

Functions: Functions are a reusable block of code that are created to execute a specific task or set of tasks. They are defined using the keyword def and may optionally have one or more parameters or and optionally a return value.

Lambda Function: The Lambda function is a simple one-line function that can be used to do computations without writing multiple lines of code.

Lists: Lists are a data type consisting of a sequential collection of values that may or may not have the same data type.

List Comprehension: List comprehensions are a concise way to create a list from another list using specifications.

Logical Operators: Logical operators are rational operators (and, or and not) used in the comparison of two or more statements to return Boolean values.

Map Functions: The map function is a function that allows for every item in a list to be used as a parameter to a function. It takes a function and a list as parameters and assigns each item in the list as an input parameter to the function.

Mutable: A data type is said to be mutable when its value can be changed or overwritten without requiring a new memory location to be assigned.

Range: Range is a Python function used to specify a counting sequence starting from one number and ending to the second one. It can be used with parameters to specify how the counting goes on.

Return Value: A return value is the output a function gives that is not directly printed but is passed along. Return values are necessary when writing a function whose output is reused. You may only have zero or one return values, not more.

Strings: Strings are a data type that has a sequential collection of zero of characters that are enclosed in single, double or triple quotes.

Variables: A variable is a value holder that needs to have a name and an allocated memory location. Variables in Python are dynamically typed, i.e. Python will automatically recognize the data type if the value changes its data type.

Parameter: Parameters are the input(s) that a function takes in when it requires one to execute its task. Parameters are defined when the function is defined. You may have zero or more parameters.