Garbage Bag (green plastic)...(polyethylene) invented by Harry Wasylyk in 1950 

Guardrail

Gestalt Photo Mapper

Green Ink...currency or greenbacks ink invented by Thomas Sterry Hunt in 1862

Hockey

Hockey Goalie Mask...invented by Jaques Plante in 1960

Heart Valve Operation (1st)

Helium as a Substitute for Hydrogen in Airships

Helicopter Trap (for landing on ships)

Hydrofoil Boat

Hair Tonic

Ice Skate

IMAX Projector & System...co-invented in 1968 by Grahame Ferguson, Roman Kroitor and Robert Kerr

Infielder's Glove

Ice Brewed Beer

Instant Potato Flakes...dehydrated potato flakes were invented by Edward A. Asselbergs, in 1962