Logic, Set theory, Graph theory, Number theory, and Combinatorics.
Logic is about Booleans. It involves identifying predicates, adding quantifiers, logical operations, and formatting conditional statements.
Set theory, found throughout the study of discrete math. It involves enumerating groups of data by organizing them into finite and infinite sets.
Number theory, using integers or natural numbers to enumerate sets of data.
Graph theory used to model pair relationships between objects. For example the relationship between the x-axis and y-axis, a simpler example: A relationship between a man and his wife. It can be used to depict diverse studies, such as a graph of social networks, a graph of network connections.
Combinatorics, the study of finite countable structures. Used in Number theory, graph theory, and probability theory.
It involves mathematical reasoning, in combination with creativity, and problem-solving.