If you've taken the subway in NY, Boston should be a breeze.
This is our subway website:
Buy a Charlie Card - and load it up!
When taking the subway be careful what platform you are on.
The subway is based on a core (Downtown) with separate colored lines taking you from the core to different areas.
All inbound trains head into downtown Boston, all outbound trains head out of Boston.
If you take the Orange line from Oak Grove you will be heading Inbound until you leave Downtown Crossing. At this point you are heading Outbound even though you have not left the train you started on.
The Boston system is much easier to navigate then NYC's. So, you should be fine.
The payment methods are a bit confusing. I will try to summarize:
Charlie Ticket: Buy at machines in stations. Cost per ride is $2. You can put as much as you want on these and keep on using until value runs out.
Charlie Card: Ask attendant in station for one. The card is free. Add value at machine. Cost per ride is only $1.70. I've never understood why the cost is different between the card and ticket. Keep adding value as you need it.
Passes: There are various passes available. A good deal is a weekly pass for $15. You can use it as many times as you want in a week.
As missingmaine says, the inbound/outbound directions can be very confusing if you are not familiar with the city and where you are in relation to the downtown area.
So, it's better to ignore any inbound/outbound directional signage and just focus on the terminus of your train which will be noted on the train itself and the platform. That way you will always know what direction you are going in.
I agree with Cabinet. And if you're ever in doubt, just ask someone "does this train go to ______".
I'll be in Boston mid-September for a week so the weekly pass sound ideal for me. Where can I buy it?
Any ticket machine located in all the T Stations.
Thank you AlanM
One thing not mentioned above that I believe needs to be mentioned is that many "T" stations have stairs only, sometimes many stairs. I won't try to list them all here, but if you have luggage, it is an issue because you are likely to face one. Many have escalators and elevators, of course. Some day they all will be accommodating.