### practical documentation for sage; e.g. %hide and %hideall
I cannot seem to find documentation on %hide and %hideall. It doesn't seem like the reference manual has any information on these two directives/commands, while the built-in command line help system just gives errors for queries like %hide? (perhaps I'm not using the correct syntax?). askSage only has a few postings on this, which are only partially helpful to me.
I guess my general question is: for someone who is still very much a novice to python and sage, how would one go about learning more about specific commands like %hide.
Also, and apologies for smuggling in a second question, how do I unhide a cell in a sage notebook after I've already hidden it with %hide?