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# Built In Functions

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You are going to learn a lot about functions later but right now we need to know how to use the functions that Python and other developers have given us. We have already seen the `print` function which allows us to print messages to the terminal.

Functions are called by specifying the name: `func` and then putting parentheses after the name: `func()`. Functions often take arguments which you will put place inside of the parentheses: `func(arg1, arg2)`. Many (but not all) functions return things from them.

## **`string <-- input('message')`**

Prints out the given message to the terminal and then waits for the user to type in a message and press enter. The message the user typed is returned from the function as a `string`.

## **`string <-- str(anything)`**

Takes any data type and converts it to a `string`.

## **`int <-- int(string)`**

Takes a `string` representation of a number (`"42"`) and converts it to an `int`.

## **`float <-- float(string)`**

Takes a `string` representation of a number (`"3.14"`) and converts it to a `float`.

## **`int <-- len(string)`**

Finds the length of a `string` (how many characters) and returns it as an `int`.

&#x20;*Try collecting some data from the user and then print out a specialized message like* *"It's a pleasure to meet you {name}"!*