handguards

A handguard (also known as the forend or forearm) on firearms is a barrel shroud specifically designed to allow the user to grip the front of the gun. It provides a safe heat-insulated surface for the user's hand to firmly hold onto without needing to worry about getting burned by the barrel, which may become very hot when firing. It can also serve as an attachment platform for secondary weapons (such as an underslung M203 grenade launcher or M26-MASS) as well as accessories such as bipods, tactical lights, laser sights, night-vision devices, foregrips/handstops, slings and a variety of other attachments.
Handguards are available in 2 different variations: free-floating and drop-in. They also use a number of mounting systems with the main ones being M-LOK, KeyMod, and Picatinny.
When talking about melee weapons, a "handguard" refers to the crossguard (also known as the quillons or crosstree), the enlarged front part of a sword, saber or knife/dagger's hilt, which protects the wielder's hands from an opponent's blade sliding towards the hilt, or prevents the wielder's own hand and fingers from accidentally slipping onto the blade when stabbing.

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