Arrays enable you to store and organize data in a list. These data structure is built-in in Python. Arrays allow you to store the data in the list without storing similar data in multiple variables. The list can be of any type, such as numbers or strings. This article will help you understand the concept of append python and how you can modify the original list. Furthermore, we will also identify the importance of append python.

What is Append Python

The append python allows you to add an item at the end of the list that is existing. You do not create a new list from append (). However, you are changing the original list. You can also add the content of one list to another.

Importance of Append

Before choosing the collection type, you should know the properties of each element and their type. This will help you to choose the most suitable type for the data set. If you want to know the suitable collection type to make a better choice, you need to know the attributes of the available types and choose one depending on the use case.

A list is similar to an array. They are different in languages. You need to select a list with the same data type. This will make it a powerful tool for Python. That is why lists and arrays differ from each other. You can include strings, integers, lists, and other data types in the list. You can alter the list after you create them. This makes the lists mutable.

When initializing the list in Python, they include a definite count and indexes. You can index an element in a list depending on the definite sequence of those elements. Furthermore, you can index the list by adding o as the first index and n-1 as the last item of the index. In this index, n is the number of items in a single list.

Each element you include in the list has its index place. That is why you can duplicate the elements as it allows you to do so. This means that we can add the same index item as a different one and the different index item while having a different index. Unlike the sets, the list will accept this index item.

Method for Append List

The method for append () in Python will help you add a single item to an old list. Your new list will not return. Instead, you will receive modifications in the original list, and a new list will join the original one from the end. The size of the new list will increase by one after you execute the append python method.


You will require one new item while performing the append python method. This single list will work as the input will join the existing list from the end. You can add strings, numbers, or some other list, such as a dictionary.

Return Value

You can only modify the original list with the append method. The value will not return; instead, you will find the modification in the list your just created.

Here is the method to add an append list in the existing list:

  1. Add New Elements In The Existing List

Below you will find how you can add numbers to the list:


# List of stringstring_list = [‘Superman’,’Batman’,’Wonderwoman’,’Flash’]

#adding a new int item to the stringlist_list.append (4)

#printing appended listprint (string_list)



  1. Add New ListIn The Existing List

Other than  adding numbers and strings, we can also include another list that we want to add in the original list:


#lets create a new listnew_list= [1,2,3,4]

#append this list to our string_liststring_list.append (new_list)

#printing appended liststring_list



The above example clearly shows that the new list appends at the end of the existing list. The whole list will include an indexed item with the help of the following code:


String_list [4]




For accessing the elements that you include in the list, you have to follow the same method to access the elements in a 2-D Matric.


String_list [4][1]



When you use the list index less than the item including index, then you will encounter Index Error:


String_list [5]


— — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — —— — -IndexErrorTraceback (most recent call last)<ipython-input-14–1d3b13a81e08> in <module>— → 1 string_list[5]IndexError: list index out of range


You can add a list of items at the end of the old list with the help of a python list append (). To add a single value to the list, you need to specify the individual items. However, if you want to add multiple values, specify the entire list. In simple words, append () allows you to add single or multiple elements in a list. Now, as you know about how append () in the Python list works, you can experiment on your own and add items to a list.