Seconded Emacs. I use it for almost everything. I started using it for text editing and it slowly crept into basic web browsing, RSS reader, word processing (with org-mode and Markdown), presentation (through Pandoc/Beamer) and Elisp/C programming. It's gotten to the point where the only four programs I use daily on my Mac are LibreWolf, FreeTube, Logic Pro and Emacs.

Seriously if I could use Logic Pro inside Emacs I would.