# What Data Type Does the Function Return?

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Angela Bailey

When working with functions in programming, it is essential to understand what data type the function returns. The return type of a function determines the kind of value that will be produced when the function is called and executed.

## Why is Knowing the Return Type Important?

Knowing the return type of a function is crucial because it helps us understand what to expect when we use that function in our code. By knowing the return type, we can assign the function’s output to variables, perform operations on it, or use it as input for other functions.

## How to Determine the Return Type?

To determine the return type of a function, you can refer to its documentation or read its source code if available. The documentation usually provides information about the expected inputs and outputs of a function, including its return type.

If you are using an Integrated Development Environment (IDE), such as Visual Studio Code or PyCharm, you can often rely on features like IntelliSense or code completion to get information about a function’s signature and return type.

## Examples of Return Types

Let’s look at some common examples of return types:

• Integer: A function may return an integer data type, which represents whole numbers without decimals. For example, a function that calculates the age based on birth year might return an integer value.
• Float: Functions can also return floating-point numbers that allow decimal values. For instance, a mathematical calculation involving division may produce a float as output.
• String: String return types are commonly used when functions need to manipulate or generate textual data.

Functions like formatting dates or concatenating strings might have string return types.

• Boolean: A boolean return type indicates that a function returns either true or false. For example, a function that checks if a number is prime might return a boolean value.
• List: Functions can also return lists, which are ordered collections of elements. A function that retrieves data from a database and returns it as a list is an example of this.

## Conclusion

In conclusion, understanding the return type of a function is essential for effectively using functions in your code. It allows you to know what kind of value to expect and how to handle it appropriately. By knowing the return type, you can confidently work with functions and leverage their outputs to achieve your programming goals.