Some define jujutsu and similar arts rather narrowly as "unarmed" close combat systems used to defeat or control an enemy who is similarly unarmed. Basic methods of attack include hitting or striking, thrusting or punching, kicking, throwing, pinning or immobilizing, strangling, and joint-locking. Great pains were also taken by the bushi (classic warriors) to develop effective methods of defense, including parrying or blocking strikes, thrusts and kicks, receiving throws or joint-locking techniques (i.e., falling safely and knowing how to "blend" to neutralize a technique's effect), releasing oneself from an enemy's grasp, and changing or shifting one's position to evade or neutralize an attack. As jujutsu is a collective term, some schools or ryu adopted the principle of ju more than others.For a full explanation about Ju Jitsu and how it has evolved read Ju Jitsu - the gentle art.