Starting with the most basic notions, this text introduces all the key elements needed to read and understand current research in the field. The first part of the book focuses on core components, including subalgebras, congruences, lattices, direct and subdirect products, isomorphism theorems, clones, and free algebras. The second part covers topics that demonstrate the power and breadth of the subject, such as Jónsson¿s lemma, finitely and nonfinitely based algebras, primal and quasiprimal algebras, Murski¿¿s theorem, and directly representable varieties. Examples and exercises are included throughout the text.