A Bow is a weapon consisting of a long wooden piece and a length of string joining both ends. Drawing the string backwards bends the wooden frame of the bow, thereby storing energy via elasticity. When the string is released, the energy that was previously used to hold the bow bent can be imparted to a projectile if one is placed against the string. The bow is used to shoot arrows - long, straight shafts (usually wooden) with a sharp head (historically metal, earlier stone) at the forward tip. Use of bow and arrow predates recorded history, and is common to most pre-industrial human cultures.
Jack O'Neill used a bow when he and his team met Apophis on Gaia. Apophis' energy shield deflected the bullets but allowed weapons thrown by hand to pass through. He believed that an arrow was slow enough to pass through the shield. (SG1: "The Nox") After the alternative Destiny expedition had settled on Novus, they began to use them for bow hunting and defense when they ran out of bullets. (SGU: "Epilogue")