Inductively Coupled Plasmas are an important type of radio frequency discharge. The plasma is electrodless and characterised by high plasma densities at low pressures. The ICP is ideal for semiconductor processing were one requires an isotropic and uniform plasma with a sufficient plasma density at low pressure. The ICP also allows for independent biasing of the substrate being processed. In this thesis an ICP with an internal antenna is characterised with the basic plasma parameters being measured as a function of input power, pressure and position within the plasma. The diagnostics used include a tuned Langmuir probe, magnetic field probe and RF current and voltage probes. The phenomena of low pressure heating in the discharge is investigated with reference to a collisionless heating mechanism. This heating mechanism is a warm plasma effect, the electrons sample the applied electric field for a time less than one RF cycle, otherwise they gain no net energy. Electron kinetics in the plasma are studied with the investigations based on the local and non-local models of electron kinetics. The local model predicts an electron energy distribution function in equilibrium with the local induced RF field, while the non-local model predicts that there is one EDF of total energy valid across the width of the discharge.