Included software packages

Hi,
Where in the IDE install would the definitive list of the classes supported for an external function that I 'include'. I see that the IDE does seem to know the syntax of the class as you roll over an Object. If I want to look see at what classes are available is that just the .h file or is there somewhere else. Say for example the SD library, I have it all working but I'm just going on what is in the examples. Some of the code seems to extend the file type and other are obvioulsy new.

Thanks
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Not sure what you are asking. You use the #include statement to include a library (sort of) that will often have classes. There are probably some built-in, but I don't know them off the top of my head. They will be documented on Arduino.cc language reference, I would think.
Yes if you turn on the appropriate IDE/compiler options, have compiled the code at least once then a hover will reveal some info and a rt click pops up a menu where you can click GoTo Definition and look at the .h file you clicked.
Does any of that help? If not feel free to follow up.