More electronic components
Single sided and double sided printed circuit boards are eathier and much cheaper to fabricate but where the space is an issue, there is nothing better than a multilayer PCB. It can house larger number of small-sized electronic components due to a possibility to provide inter-connectability between multiple layers.
A multilayer PCB is made by combining several thin printed circuit boards. These boards are etched in separate processes and then glued together into a multilayer PCB. It contains trace layers inside the board providing connection between layers. A component housed on the outer layer of a PCB can have a connection with any layer via specially fabricated micro-holes that has been made using finest drills.