Shaliah Tzibbur
The person leading the congregation in public prayers is called the shaliach tzibbur (Hebrew for "Jewish legal emissary of the congregation"), a ħazzān or sometimes called the cantor. Jewish law restricts the role to Jewish males over the age of 13. See also: Cantor in Reform Judaism. In theory, any lay person can be a sheliach tzibbur; most synagogue-attending Jews will serve in this role every now and again. In practice, those with the best voice and the most knowledge of the prayers serve much more often.
There are many rules relating to how a cantor should lead services, but the idea of a cantor as a paid professional does not exist in classical rabbinic sources. Jewish prayer services are collected in a prayerbook known as the siddur.
Read more about this topic: Hazzan