what is a 'seven-thirty local' ?

[muribad]

dear teachers,

could you tell me what these words mean?
They come from a book entitled "Q & A" (the "slumdog millionaire" story).
I couldn't find it in any on-line dictionary.
It's only the second page of the book and I've already hit a snag!

Here is the complete sentence :
"My departure from Asia's biggest slum would make no difference to their lives. There would be the same queue for water in the morning, the same daily struggle to make it to the seven-thirty local in time."

[David L.]

I'm not sure what 'they' refers back to, but the context is, that a book entitled Q & A was adapted into a film called Slum Dog Millionaire.
Since a lot of people are going to be far more familiar with the movie than with the book, when he refers to the book - "Q & A" - he indicates that it is the story in that book which became the film Slum Dog Millionaire - it's the Slum Dog story.
(Slum Dog is just a short way of referring to the film without saying the whole title.)

seven-thirty local (in time): 7.30 a.m.(or p.m.) train which operates within the city limits ( a local train and not an InterCity or other long-distance train.)

Each day it's a struggle - he has to hurry himself - to be in time to catch the 7.30 a.m. train, that will take him to some other part of the city - to take him to work.