It is a pronoun used to refer to a male person who is the subject of a sentence.
Here are some examples:
* 他是医生。 (Tā shì yīshēng.) - He is a doctor.
* 他喜欢游泳。 (Tā xǐhuan yóuyǒng.) - He likes swimming.
* 他住在北京。 (Tā zhù zài Běijīng.) - He lives in Beijing.
It's important to note that "ta" can also be used as a neutral pronoun for when the gender of the person is unknown or irrelevant.