In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for the diameter of a sphere. The word "diameter" is derived from Greek language διάμετρος ( diametros), "diameter of a circle", from δια- ( dia-), "across, through" μέτρον ( metron), "measure". Online Etymology Dictionary It is often abbreviated ..
vCard is a file format standard for electronic . vCards are often attached to e-mail messages, but can be exchanged in other ways, such as on the World Wide Web or instant messaging. They can contain name and address information, , e-mail addresses, URLs, , , and audio clips.
Wireless is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few metres for television remote control, or as far as thousands or even millions of kilometres for deep-space radio communications. It encompasses various types of fixed, mobile, and portable , cellular telephone, (PDAs), and . Other examples of wireless technology include GPS units, or garage doors, wireless computer mice, keyboard and Headset, , , satellite televisi..