tasks = ['email Tom', 'call Max', 'meet with sister']
print(tasks)

Let's say that we completed the first thing from this list; that is, we have already written an email to Tom. To strike that element off the list, we write:

tasks = ['email Tom', 'call Max', 'meet with sister']
del tasks[0]
print(tasks)

Now the list has two elements:

`tasks[0]` is 'call Max'

`tasks[1]` is 'meet with sister'

We can delete any list item by specifying its index number.

> Note
>
> What about the syntax of the `del`?
> - The statement begins with the keyword `del`.
> - Then we usually specify the list item using index `tasks[index]`.

What is a list? A list is a collection that is ordered and changeable. Moreover, this collection allows duplicate elements.

What is a dictionary? A dictionary is an ordered and changeable collection with no duplicate members. A dictionary holds `key:value` pairs. Key-value is provided in the dictionary to make it more optimized. 

What is a tuple? A tuple is a collection that is ordered and unchangeable. This collection allows duplicate elements. A tuple is a collection that is very similar to a list. The sequence of values stored in a tuple can be of any type, and they are indexed by integers. Values of a tuple are syntactically separated by ‘commas’. Although it is not necessary, it is more common to define a tuple by closing the sequence of values in parentheses. This helps to understand the Python tuples more easily.

What is a set? In Python, a `set` is an `unordered collection` of data type that is `iterable`, `mutable` and has `no duplicate elements`. The order of elements in a set is undefined, though it may consist of various elements. The major advantage of using a set as opposed to a list is that it has a highly optimized method for checking whether a specific element is contained in the set.

Python Data Structures

Deleting Elements

Task