There are two main ways to combine multiple tables or geographic features together.
(1) First is a tabular join, where attribute tables are joined together based off of a common field.
(2) Second is a spatial join, where two geographic feature classes are joined together based off where they physically intersect each other.
Both types of joins are access by right-clicking your target feature class in the table of contents and select 'Joins & Relates/Joins...'.
