Runway Maintenance refers to activity required to keep the runway in a safe condition for aircraft use. The integrity of runway surfaces and lighting is assured by regular inspections.
The purpose of runway inspection is to assess and to report the actual conditions of the runway in terms of “dry”, “wet”, “water accumulation”, etc.
The purpose of runway lighting inspection is to make sure that the lighting system is working.  It also aims to identify any components of the system that would not be working.
The purpose of visual aids inspection is to make sure that these systems are working, from an electrical point of view