Algebra is a branch of mathematics.

Algebra may also mean:

• elementary algebra
• abstract algebra
• linear algebra
• universal algebra
• computer algebra
• Boolean algebra, in formal logic
• algebra over a commutative ring (or R-algebra), in ring theory

In set theory:

• algebra over a set
• sigma algebra

In linear algebra, and the study of vector spaces:

• algebra over a field
• associative algebra

In category theory:

• F-algebra
• F-coalgebra

Algebra (Begriffsklärung)