The Four Basic Data Structures

The Four Basic Data Structures

1. Lists

   • Used to store multiple items in a single variable. List items are ordered, changeable, and can have duplicate values. List items are indexed. Written with normal brackets

2. Tuples

   • Used to store multiple items in a single variable. A tuple is a collection which is ordered and unchangeable. Tuples are written round brackets In order to determine how many tuples there are, use the len() function.

3. Sets

   • Used to store multiple items in a single variable. Sets are unordered, unchangeable, unindexed, and do not allow duplicates. Written with squiggly brackets.

4. Dictionary

   • Used to store data values in key:value pairs. A dictionary is a collection which is unordered, changeable and does not allow duplicates. Dictionaries are written with curly brackets, and have keys and values:

5. So what is the difference?

   • List is a collection which is ordered and changeable. Allows duplicate members. Tuple is a collection which is ordered and unchangeable. Allows duplicate members. Set is a collection which is unordered and unindexed. No duplicate members. Dictionary is a collection which is unordered and changeable. No duplicate members.