Connectivity  The ability of a computer to communicate with others Sending Device Communications Device Communications Channel Communications Device Receiving Device

 What types of sending and receiving devices are there?

There are two ways of sending data via a communications channel. 1. Analog – information is stored in the modulation of waves (modulate = change size or spacing). AM – amplitude modulation FM – frequency modulation

2. Digital signals rely on a stream of on/off pulses. The pulses are repeated in case some sections are missed.

 Modem is short for Modulator-Demodulator. It converts analog signals into digital signals and vice versa.  Example: speaking into a telephone produces an analog signal. It can be converted to digital to be sent along the phone lines.

 A wireless laptop or mobile phone (or other mobile device) is said to be ‘web-enabled’ if it can access the internet and . NETWORKS  A network is a collection of computers and devices connected by communications channels.  This facilitates communications and allows sharing of resources.

 What advantages are there to networks?