Atoms are composed of three type of particles: protons, neutrons, and electron. Protons and neutrons are responsible for most of the atomic mass e.g in a 150 person 149 lbs, 15 oz are protons and neutrons while only 1 oz. is electrons. The mass of an electron is very small (9.108 X 10-28 grams). Both the protons and neutrons reside in the nucleus. Protons have a postive (+) charge, neutrons have no charge --they are neutral. Electrons reside in orbitals around the nucleus. They have a negative charge (-). It is the number of protons that determines the atomic number, e.g., H = 1. The number of protons in an element is constant (e.g., H=1, Ur=92) but neutron number may vary, so mass number (protons + neutrons) may vary.
Payment Card Industry Data Security Standard (PCI DSS) compliance is adherence to the set of policies and procedures developed to protect credit, debit and cash card transactions and prevent the misuse of cardholders' personal information. PCI DSS compliance is required by all card brands. Download this free guide.
The Peripheral Component Interconnect or more commonly known as PCI is a standard for connecting a lot of devices inside your computer to extend its capabilities. Devices like sound cards, modems, NIC, TV Tuners, and some video cards have at some point or another have used the PCI port. The latest version of PCI known as PCI express is a much improved version in terms of speed. PCIe uses a serial interface instead of the old parallel interface used by PCI. It also utilizes individual buses for each of the devices connected to it instead of a shared one like what PCI uses.