OneNote 2016 - lecture notes or rough calculation using stylus or typing Xmind - overview of everything in my mind in form of mindmap Notepad/Sublime - scatte

OneNote 2016 - lecture notes or rough calculation using stylus or typing Xmind - overview of everything in my mind in form of mindmap Notepad/Sublime - scattered notepad files on my desktop symbolize sticky notes or reminders Mathematica 11 - Math & Physics equations with their interactive graphs and my notes on them, can be exported in TeX Excel 2016 - Time Table, Daily routine, monitoring budget or expenses, time spent in various activities, my progress day by day Powerpoint 2016 - writing contextual notes just under the duplicate copy of original slides TeX - Formal notes worthy of sharing with others, I use the textbook templates available online vim+ranger - saved code snippets and related notes Sigil - annotation and note taking over epub textbook or novel Adobe reader/PDF Expert - annotation and note taking over pdf textbook or novel or paper Scrabook X (Firefox addon) - annotation and note taking over web pages, data can be later exported as epub file Zim - Journal Sound recorder - audio note just as a back up in a case I missed something during lecture Video camera - explaining a point to your future self I hope this helps.