This comment here, set me off to find which constituency I belong to. It turned out that there's not one, but three. That's because there are three elections in which we vote - Bombay Municipal, Maharashtra State and the General Elections.
Here are the details of each election and the relevant constituency (purely from Mumbai's perspective)
1. Municipal Corporation of Greater Mumbai (MCGM/BMC) -
Last held: Feb-2007
We vote for: Councilor
Division: Into 227 electoral wards, clubbed under 27 administrative wards
Numbering: Electoral Wards are numbered 1 to 227. Administrative wards are from "A" to "T"
For example, Pali Hill and Lilavati Hospital are both in Bandra. But Pali Hill falls under electoral ward no. 96 and Lilavati Hospital under electoral ward no. 97. And both wards (nos 96 and 97) fall under Ward H/West. So, there are 227 electoral wards (and hence 227 councilors) clubbed under 24 administrative wards. The electoral wards are numbered 1 through 227 and the administrative wards are numbered A through T.
To know which electoral ward you stay in (it will be numbered between 1 and 227), read my earlier post on the BMC elections. Or, if you're willing to put in the effort, download this very detailed powerpoint presentation here, which gives the boundaries of each and every electoral ward. The presentation has (obviously) 227 slides and is in Marathi.
2. Maharashtra State Elections:
Last held: October 2004
We vote for: Member of Legislative Assembly
Division: Mumbai City and Mumbai Suburban
Numbering: 34 Assembly Constituencies. 17 each in Mumbai City and Mumbai Suburban as below (source here)
3. General Elections:
Last held: May 2004
We vote for: Member of Parliament
Division: No sub division
Numbering: Six Parliamentary Constituencies numbered 4 to 9 as below (Source)
4 - Mumbai South
5 - Mumbai South Central
6 - Mumbai North Central
7 - Mumbai North East
8 - Mumbai North West
9 - Mumbai North
Looking at the above, it makes sense, doesn't it? Locality, City and Country. I have the right and duty to vote for the person in charge of all three. If you look at any political party poster in your area - and assuming they all belong to the same party - then you'd probably find the mugs of the Municipal Councilor, Member of Legislative Assembly (MLA) and Member of Parliament (MP) on it.
To put things in perspective, Mumbai has 227 councilors in the BMC, 34 MLAs in the State Assembly and 6 MPs in the Parliament. These are the people you elect, these are the people responsible for your area and these are the people who represent it in the Municipality, Assembly and Parliament.