1 In 1995, RSA sent a handful of people across the hall to found Digital Certificates International, better known as VeriSign. 2  The company then called Security Dynamics acquired RSA Data Security in July 1996 and DynaSoft AB in 1997.
Printed circuit board with components attached. A printed circuit board (PCB) is a plastic board made for connecting electronic components together. These are used in almost all computers and electronics today. The card is made of a material that does not conduct electricity, like fiberglass or plastic.
Four Layers (4L), Six Layers (6L), Eight Layers (8L), Ten Layers (10L) Board with more than 10L. In fact, for board more than four layers, people will named it Multi-layer PCB. According to that standard, there're only three types of PCB: Single, Double and Multi-layers. In a word, according to different standard, FR4 PCB can be divided into different classfication.