自爆是指爆炸物自行爆炸，亦可指对自己使用的兵器和机械进行破坏。

自爆大致可以分为三种。

1. 爆炸物因为意外事故而爆炸。
2. 火箭与导弹偏离目标时，为了避免误伤而自行引爆。
3. 牺牲自己，进行自杀式爆炸攻击的恐怖活动。

Self-destruct is a mechanism (protocol or device) that can cause an object to destroy itself within a predefined set of circumstances. The self-destruct mechanism is usually the most complete way to destroy the object. For that reason the self-destruct mechanism can be used to destroy objects that are meant to be discarded.