H

H/W

Hardware (the slash is optional)

HAL

Hardware Abstraction Layer

HAL

Heuristically programmed ALgorithmic computer (as in H.A.L. 9000)

HD

Hard Disk

HD

High Density

HDD

HD Drive

HDML

Handheld Device Markup Language

HDSL

High data rate DSL

HDTV

High Definition TV

HDU

HD Unit

HDVD

High-Density Volumetric Display

HFS

Hierarchical File System (Mac OS, Apple)

HK

HåndboldKlub [handball club]

HP

Hewlett-Packard

HPGL

HP Graphics Language

HR

Human Resources

HTH

Hope This Helps

HTML

HyperText Markup Language (a SGML DTD)

HTTP

HyperText Transfer Protocol

HTTPS

HTTP Secure