Henry Louis Aaron, a baseball player

Human leukocyte antigen, a key part of the human immune system, or the paternity test based upon it

Hot Lesbian Action, a WWE segment used by Eric Bischoff

House of Lords Act, a UK constitutional reform

Harvey L. Atwater, a U.S. politician

High Level Assembly, an Intel 80x86 Assembly Language, originally written as a teaching aide by Randall Hyde

Hidden Lake Academy, a boarding school

High Level Architecture, a distributed computer simulation standard

Human Life Amendment, a proposed constitutional prohibition of abortion in the United States

Hapag-Lloyd Airlines, a German charter airline

Hydraulic Lash Adjuster, a device for maintaining zero valve clearance in an internal combustion engine.

High-level assembler, a generic term for assembly language translators that incorporate features found in modern high-level programming languages into an assembler.