SQL (Structured Query Language) is a standardized language used to manage and manipulate data in relational databases, handling tasks such as querying, updating, and organizing data.
A primary key uniquely identifies each record in a table and ensures each entry has a distinct, non-null identifier, enforcing data integrity.
A foreign key is a field in one table that creates a relationship with the primary key of another table, linking related data across tables.
A data type specifies the kind of data a column can hold, such as integers, strings, dates, or binary data.