Give me in detail

Hello sasikanth

A fluorescent light has very little electrical resistance. The choke has three functions :

1 - to limit the current during normal operation.
2 - to limit the current through both filaments during starting.
3 - to start the tubelight discharging.

A choke is a coil. Interupting the current through a coil (by the starter) produces a short peak voltage. This starts the discharge in the tubelight.
During starting the higher current heat both filaments to support starting.

Diagram of fluorescent light (tube light)

A = fluorescent lamp
B = electricity supply
C = starter
D = Bi-metal contact
E = Noice suppressor
F = 2 filaments
G = Choke

I don't know

A starter is actually a capacitor connected in parallel with a fluorescent lamp.
To strike a f.lamp a sudden spark of current discharge is required in the tube.the starter supplies this initial spark.
When a tube light arrangement is connected to the supply,the starter charges(charging is as in a capacitor).a starter current flows during this session.
On reaching the striking voltage(the voltage just needed to flash the light for the first time) the starter discharges and a sudden current flows in the tube ionising the gas and giving it the glow.
After this starter current becomes nil.
For more details and circuit diagrams,see the link.
http://en.wikipedia.org/wiki/Fluorescent_lamp#Mechanism_of_light_production