Dictionary comprehension is a concise way to create dictionaries in Python using a single line of code. It follows the format {key: value for item in iterable if condition}.
List Comprehension: A concise way to create lists using the format [expression for item in iterable if condition].
Nested Dictionary: A dictionary where values can also be dictionaries, allowing hierarchical data storage.
Iterable: \text{An object capable of returning its members one at a time, such as lists, tuples, and strings}.