All matter such as solids, liquids, and gases, is composed of atoms. Therefore, the atom is considered to be the basic building block of matter. However, atoms are almost always grouped together with other atoms to form what is called a molecule. Only a few gases such as helium are composed of individual atoms as the structural unit. Atoms are extremely small.
What is the Difference between USB Type A and USB Type B Plug/Connector? In the Catalog for USB-232/485 Series Interfaces, it says that the 1-port interface has a USB Type A plug whereas the 2- and 4-port interfaces have a USB Type B connector. What is the difference?
Type A and Type B Ports. All USB devices have sockets, and all the cables have plugs. Host sockets are Type A, and peripheral sockets are B, Mini-B or Micro-B. For expansion, hubs have a B or Mini-B socket to connect to the computer and several Type A sockets for devices (see USB hub).