While there aren't that many items to pick up and use in Half-Life, the few that are in the game can make the difference between life and death. Many of these items can also be found in crates, so be sure to use that crowbar to break them open.

Air Tank

Air tanks allow the user to survive underwater for extended periods of time - a situation in which the HEV suit provides almost no help.

Batteries

Individual batteries help increase the HEV suit's power by 15 points - up to a maximum of 100 percent.

Health Kit

Individual Health Kits increase your health by 15 points - up to a maximum of 100 percent.

HEV Suit

Picked up early in the game, a powered-up HEV suit provides protection against many forms of energy and weather, and it can also help bring the wearer's health back to normal, though many of the functions come at a cost to the suit's power supply.

HEV Suit Charger

Mounted on the wall, the HEV Suit Charger must be accessed by the Use key in order to work. The Suit Charger can increase the charge by as much as fifty points before deactivating.

Long Jump Module

This module adds a long-jump capability to the HEV suit, giving the wearer the ability to make (believe it or not) extremely long jumps.

Soda Can

Found in the vending machines scattered throughout the laboratories, Soda Cans can increase health by two points - up to a maximum of 100 percent. Press any of the buttons to dispense a can.

Wall-mounted First Aid Kit

The Wall-Mounted First-Aid kits can be accessed by the Use key, and can increase your health by as many as forty points before shutting down.