The inevitable “what’s your favourite editor and why” topic. I think all tech related forums have them!
I’ve been through a lot of them and, obviously, there is a time and a place for each. However, I seem to have bonded mostly to Emacs, especially in non window mode. I’ve gotten used to all the keyboard shortcuts and vast sea of extensions have been of great use. Not to turn this in a Vi vs Emacs as I also really do like vi as well. I’ve also dabbled with Sublime.
IDE wise, that’s quite easy. In day-to-day work, I’m a Python developer, so I use PyCharm because it is really a good product. For the most part “it just works” and has some really clever features build in, like deployment. I used to use Eclipse with PyDev, but after a year-and-a-bit of playing, could never get it stable (especially with the eGit plugin).