When does an electric short-circuit occur?

Explanation

A common type of short circuit occurs when the positive and negative terminals of a battery are connected with a low-resistance conductor, like a wire. With a low resistance in the connection, a high current will flow, causing the delivery of a large amount of energy in a short period of time.
In simple terms, a short circuit gives electricity the path of least resistance between two conductive points. Less distance between the two points means less resistance, which means your short circuit will produce more heat and result in burns and fires.