What is an oxidizing agent?

A substance that tends to bring about oxidation by being reduced and gaining electrons

An oxidizing agent is a substance that takes negatively charged electrons "away" from a substance or object; usually taking these electrons for itself it can also transport the electrons from an object and "give" them to another substance or object. The object that has been oxidized will then have a positive charge after losing the negative electrons and the substance receiving the electrons will become negative.

Explanation:

Examples include halogens, potassium nitrate, and nitric acid.