fluorescent lamps  The  fluorescent  tube contains argon and mercury gases at low  pressure.  When  there is a current flowing through it, moving electrons  collide with mercury atoms and UV radiation is emitted. The  inner  side  of  the  tube wall  is coated with phosphor powder which absorbs UV radiation and reemits light. This process is called flurescence.

High  voltage  is  necessary  to start the current for which starter  is required. Once started very low current is necessary. Choke (inductor) is used to reduce the current.