It's not widely used in american english but is in british english...! "Learn the ropes" means to learn something new, say a certain job or an activity. e.g. - " They have to spend more time to learn the ropes. " Means: To learn a certain job or activity, they have to spend lot of time...! Think it helps...!

I don't think it's specific to the US, but it means to learn the basics about something. You can learn the ropes at a new job. http://www.phrases.org.uk/meanings/225200.html