How to Use “join” in Python

This tutorial discusses how to use the “join” method in Python. Python provides several built-in methods ready for us to use at any given point, and one of them is the join() method. It is a string method that allows us to concatenate a string ‘separator’ with all the elements within a list or any iterable.

Step 1: Understand the basics of ‘join’

The join() method in Python is primarily used to join or concatenate elements of an iterable (such as a list or a string) into a single string. The syntax for it is: ‘separator’.join(iterable). Here, the ‘separator’ is the string that gets inserted in between the elements of the iterable. For instance, if our list is [1,2,3] and the separator is “-“, we’d get “1-2-3”.

Step 2: Using ‘join’ without a separator

Without a separator, all the items in our iterable get joined into one string.

For example:

The output would be: ‘1234’.

Step 3: Using ‘join’ with a separator

If we want to add a separator between the items in our iterable, we just indicate it in the method-

For example:

The output would be: ‘1, 2, 3, 4’.

Step 4: Using ‘join’ with different data types

Bear in mind that the join() method only works with strings. Thus, if the iterable contains any non-string values, it will throw an error. To avoid this, you can use a simple loop or list comprehension to convert the items into strings before applying the join method.

For example:

The output would be: ‘1, 2, 3, 4’.

The Full Code


The join() method is a useful function in Python that helps in concatenating or joining elements from a list or any iterable. Despite the simple idea behind it, it’s a powerful tool when working with large amounts of data.

However, it’s important to remember that it only works with strings. Thus, make sure to convert your data to the string data type before using this method.