What is an F.I.R.
The full form of F.I.R is First Information Report. The police officer on duty records the information,given by the aggrieved person or any other person about the commission of an alleged offence. On the basis of the F.I.R. the police starts its investigation.
Who can file an F.I.R.
Anyone can file an F.I.R. It does not have to be the aggrieved person. The information need not be by the person who has had firsthand knowledge of the facts. It can also be hearsay.
Where to file an F.I.R.
Any police station can record an F.I.R in whose jurisdiction the offence has occurred. It must be made to the officer-in-charge of the police station, in his absence, the Assistant Sub Inspector is competent to enter upon the investigation
How to file an F.I.R.
The procedure to be followed by an aggrieved party to file an F.I.R when a wrong is committed:

• Meet the officer-in-charge in the police station.
• Step by step in an orderly sequence narrate to the officer all the information that relates to the commission of the offence.
• The officer should reduce the information given in writing.
• The person giving the information should sign it.
• The information given will be entered in a book to be kept by the officer.

Copy of the information as recorded shall be given to the informant, cost free.
Where an officer-in-charge refuses to record the information
If the officer in charge refuses to record the information, send the information in writing and by post to the Superintendent of Police who if satisfied that such information discloses the commission of a cognizable offence, shall either investigate the case himself or shall direct an investigation to be made by any police officer subordinate to him.
Once the F.I.R. has been registered, the investigation of the case shall begin.
Investigation By Police:
In criminal proceedings, as soon as a police officer receives information about the commission of an offence he is entitled to start investigation of the matter. Investigation includes collection of evidence conducted by a police officer or by any person who is authorized by the Magistrate in his behalf.
Your rights

1. A person need not answer to answer that would expose him to a criminal charge or to a penalty or forfeiture.
2. A person making a statement to a police officer in the course of investigation need not sign it, if it is in writing.

• A police officer shall not prevent any person from making in the course of any investigation any statement, which he may be disposed to make of his own freewill.

Your duties

1. A police officer making an investigation may, by order in writing ask any person who resides within the local limits of his own or adjoining police station to come to the police station for questioning and such a  person is duty bound to report on the specified time and place.
2. Such person is bound to answer truly to all questions relating to the case the police officer puts forward to him.
3.  A police officer or other person shall not offer or make any such inducement, threat or promise to the person being questioned.