i think jail & prison r same,jail is telugu word, jail is called in english as prison 

none I think... Americans use the word prison. just like, diff between apartment and flat....

Prison: Safe building where criminals can be kept locked up after they have been convicted or while they wait trail, 

Jail: Noun, Prison, place where criminals are kept, 

Verb: To put some one in prison. 

Do you agree that jail is before conviction and prison means after conviction?

YES ASSUMMI JI

Prison is certainly after conviction. In jail, both undertrials and convicts can be detained.

A jail is a short-term detention facility.

Prisons are conventionally institutions which form part of the criminal justice system of a country, such that imprisonment or incarceration is a legal penalty that may be imposed by the State for the commission of a crime.

Apart from other replies here, I find that jails don’t have many amenities for people serving time there, since they won’t be there for very long (although a jail sentence can seem like a very very long time). A county jail may have a work release program and services to combat substance abuse and address vocational needs of its inmates — or it may provide only the basic necessities of housing, food, and safety.

Prisons often have work release programs, a halfway house service, classrooms for vocational training, and recreation and entertainment facilities. Some prison inmates are going to be there for decades or for a lifetime.

suchithra S has given a near correct answer

A place for the confinement of persons in lawful detention, especially persons awaiting trial under local jurisdiction is known to be JAIL

 whereas PRISON is a correctional institution where persons are confined while on trial or for punishment

Interesting observation from Learned members .

Why are words JAILER and PRISONER so different in meaning?