PCB or printed circuit boards are basically used to electrically connect the electronic components using conducting pathways, tracks and even signal traces. It is made by etching the copper sheet on the non conducting substrates. A PCB including the electrical components is known as PCA(printed circuit assembly)
They are inexpensive and highly reliable. The production is simpler too by automated equipments.
The conducting layer is usually made of copper whereas the dielectric or the insulating part is made of teflon, FR-2, FR-3 etc.
There are various operations performed in the formation of a PCB like drilling, lamination, etching, screen printing, testing etc.
For those interested in PCB designing and not actually performing the various operations a company expressPCB provides a free PCB software. You can design your PCB for free, the charges will only apply if you get it printed and that too a nominal charge of $51 for a 2.5"x3.8" board.
