Pointing is the finishing of the joints in brick masonry using either cement mortar (1 (cement): 3 (sand)) or lime mortar (1 (fat lime): 2 (sand)). 
Facing is an outer layer or coating applied to a surface like brick wall for protection or decorative purpose. 
Guniting is the process of repairing the already damaged concrete surface. In this method, cement is mixed with sand in 1: 3 or any other specified proportion and this mixture is applied over damaged concrete surface with a cement gun under some pressure. By doing so, a highly impervious surface is achieved. 
Plastering is the process of covering rough walls and uneven surfaces in with a material, called plaster, which is a mixture of lime or cement and sand along with the required quantity of water