Persons of the age of 18 years shall be considered of age and until they attain that age, shall be minors. Whenever referred to in the laws of this State, a person who is an adult or who has attained majority shall be a resident or nonresident person of 18 years of age or more. (Amended 1971, No. 90, § 1; 1971, No. 184 (Adj. Sess.), § 1, eff. March 29, 1972.)