UNHRC is a committee in the United Nations that monitors the implementation of International Covenant on Civil and Political Rights (ICCPR). ICCPR presents the list of humans rights to which every State parties in the UNHRC committee agrees and works on the implementation of the rights in their respective countries.

Read the ICCPR here- http://www.ohchr.org/EN/ProfessionalInterest/Pages/CCPR.aspx

UNHRC consists of a body of 18 independent experts who are competent in the field of  human rights. Reports should be submitted by the 168 UN member states on their compliance with ICCPR every five years. The members of the Human Rights Committee, who must have a well-defined moral character and recognized expertise in the field of human rights are elected by the member states. They serve four-year terms, with one-half of their number elected every second year at the General Assembly.

UNHRC main function includes-

i) Reporting of the implementation of human rights.
ii) Considering Individual Communications in cases where an individual claims that his or her rights under the covenant  has been violated by the State Party.
iii) Issuing general comments to clarify the scope and meaning of various articles and obligations of State Parties.
iv) Consider Inter-State complaints in cases where one State Party files complaint regarding the poor implementation of Human Rights of another State Party.