In an autoloading firearm
the charging handle is the external control lever
that allows the operator to manually manipulate the action be it for chambering
, clearing, or function testing.
The charging handle is usually attached to the breech block, or bolt and also moves along with it when the gun is cycling. Keep your hands free from the charging handle when firing as you could get hurt if you catch it on its travel.
The charging handle can be found on the right side of the firearm on side ejecting rifles like the Marlin 60 but can also be on the rear like on the Steyr TMP or the AR 15.