A list finds things by position: item 0, item 1. Often you want to find things by name instead: a phone number by a person's name, a price by a product. That is what a dictionary is for. It stores pairs of keys and values, inside curly brackets:

prices = {"tea": 1.80, "coffee": 2.50, "cake": 3.20}
print(prices["coffee"])
print(len(prices))
print("cake" in prices)

Each pair is written key: value, separated by commas. You look a value up with its key in square brackets. in checks whether a key exists.

Keys are usually strings or numbers, and each key appears only once. Values can be anything: numbers, strings, lists, even other dictionaries.