Air-conditioned first class (AC1)

Spacious and carpeted (and lockable) 4-berth and 2-berth compartments with washbasin.  All necessary bedding is provided, and berths convert to seats for daytime use.  AC1 is a very comfortable and civilised way to travel, although it is found only on the most important long-distance trains and costs about twice the price of AC2.  In AC1, you'll be mixing with bank managers and army officers.  You cannot specify that you want berths in a 2-berth rather than a 4-berth compartment when you book - specific berth numbers are only allocated by Indian Railways closer to the departure date and shown on reservation lists at the station before departure and on the coach side.  Couples are normally given preference for the 2-berth coupés, families and passengers travelling alone are normally allocated berths in one of the 4-berth compartments, but of course this can't be guaranteed.  Centre picture:  A rather nice AC1 2-berth 'coupé' with fabric-covered seats / berths on the Kalka-Delhi-Howrah Mail.  Below left:  An AC1 4-berth compartment on the Bombay-Howrah Mail with the the more usual brown leatherette seats and berths...

Air-conditioned 2-tier (AC2)

AC2 provides seats by day, convertible to bunks at night.  AC2 coaches are not divided into separate compartments, but are open-plan, with berths arranged in bays of four (two upper, two lower) on one side of the aisle, and in bays of two along the coach side above and below the windows on the other side of the aisle.  Each bay is curtained off for privacy, and an attendant distributes pillows, sheets and blankets in the evening.  AC2 is found on almost all decent long-distance trains, and it is the way the Indian middle classes travel.  It's relatively clean and uncrowded, and a good choice for most visitors to India.

Right:  A bay of 4 berths in an AC2 sleeper.  The seat back folds down to form the bottom bunk.

Far right:  The aisle in AC2.  Bays of four are to the right, bays of two on the left.

First class

Non-air-conditioned coaches with lockable 4-berth and 2-berth compartments.  Bedding is not included in the fare, but may be available for a small extra charge if booked in advance.  Non-AC 1st class  accommodation has now almost disappeared, as Indian Railways have largely phased it out in favour of AC 2-tier.  It is generally grubbier than either AC1, AC2 or AC3 as it is not sealed against the dirt.

AC Executive chair class

AC Executive Chair Class is only found on the most important 'Shatabdi Express' trains, for example Delhi to Agra.  It is available to holders of an AC1 IndRail pass.

AC Chair class

Comfortable air-conditioned seating cars.  AC Chair Class is found on a number of 'intercity' daytime trains (for example Delhi-Jaipur, Delhi-Agra, Delhi-Kalka for Simla), and is available to holders of a AC2 class IndRail pass.  A good choice for daytime travel..!

Sleeper Class

This is the way most of the Indian population travels long-distance, and the majority of cars on a long-distance train will be sleeper class.  Sleeper class consists of open plan berths with upper, middle and lower bunks arranged in bays of six on one side of the aisle, and along the coach wall in bays of two (upper and lower) on the other side of the aisle.  Bedding is not provided, so bring a sleeping bag.  Sleeper class is found on almost all long-distance trains except for the premier 'Rajdhani Express' services.  Sleeper class can be quite crowded (although in theory all berths must be reserved, so it can't get overcrowded), and it's fairly grubby and basic.  On the other hand, you get a better view of the countryside then in AC coaches, where the windows are sealed, tinted, and sometimes dirty.  In summer, there are fans on the ceiling and a breeze from the windows.  In winter, wrap up warm at night and take a sleeping bag and fleece, as it can get cold.  Sleeper class is used by the more adventurous backpackers, who are prepared to take the rough with the smooth...

Sleeper class windows are fitted with bars to keep out intruders. There is a glass pane and a shutter both of which can be raised / lowered.

A bay of six in sleeper class, showing seats in daytime mode on the left, and berths in nighttime mode on the right.

The aisle of a sleeper class car.  Bays of six to the right, bays of two on the left.  Remember to bring your own bedding..!

2nd class seating car.

Some trains have padded plastic 2nd class seats...

...others have wooden seats.