A Dictionary (or "dict") is a way to store data just like a list, but instead of using only numbers to get the data, you can use almost anything. This lets you treat a dict like it's a database for storing and organizing data.
A dictionary can be organized as key value pair.
Let us take for example a real dictionary. Where there is a word, and there is the meaning associated with it. We can look up the meaning, if we have the word with us. Same way, dictionaries in computer science have key and value.