There are 6 train berth types on Indian trains. They are different in their sizes and accessibility. The berth types are,
Lower berth
Middle berth
Upper berth
Side lower
Side middle
Side upper
A train berth is a bed where you can lie down. Sleeper coaches usually have 8 berths with two of them on the sides. The window seats belong to the lower berth, the seats next to these are middle and the ones near the aisle are upper.
The side berths are the set of two window seats, along the aisle. They are called the side lower and side upper berth. Usually, sleeper coaches do not have such berths. In rare cases, trains like Gareeb Rath, there will be an additional side middle berth.
The different types of train berths are explained below.
Lower Berth
The window seats are the lower berths which are the most convenient and most preferred. These seats are the most enjoyable as they give you a direct view of the exterior. Those occupying these berths will have no difficulty finding out which station they have reached. You just need to take a look through the window. In addition, you have easy access to the table between the two lower berths if needed.
At the same time, lower berths are now part of the reserved quota for senior citizens and women of a certain age. Thus, such train seat availability is not open to all.
Middle Berth
Middle berths, as the name suggests, are in the middle. The backrest of the seats is lifted and secured with the two chains provided to make the middle berth. This is the least comfortable of all the train berth types. There is not much room between the middle and upper berths, just room enough to lie down.
The only saving grace here could be the easy access to charging ports and even the switches that control the lights and fans.
Upper Berth
The upper berths are the topmost on both sides. You need to step on the ladder provided to reach the upper berth and it is the least convenient berth. The upper berth will be inconvenient for tall people. However, it can be better than the other two berths with a bit more headroom.
The only positive aspect of this berth is that you can sleep without causing inconvenience to others. The middle and lower berths do not have this privilege; one can use these berths to sleep only from 10 pm to 6 am. If you did not choose any berth, you can confirm the berth allotment by checking the PNR status.
Side Upper Berth
The upper berth along the aisle is called the side upper berth. You can access this berth by going to the ladder provided. It is convenient only for sitting comfortably. It can be convenient for almost everyone except young children. The biggest advantage here is that you can access it anytime you want.
Side Lower Berth
The lower side berth is the best one for enjoying the views outside. This is comfortable and easily accessible. Just fold down the backrests of each seat and lock them to make the berth ready. This berth is also given to those with a RAC ticket where they share a seat. The berth gives enough space to sit comfortably. The biggest disadvantage of this berth is that it is along the aisle where people often walk through.
Side Middle Berth
This is a rare berth seen only in selected trains. If you are on a waiting list and are uncertain about your berth, you can find the allotted berth after the IRCTC chart preparation.