<i>Part of me wants to just hand-write them and then maybe scan them, but that&#x27;s not searchable&#x2F;indexable, and doesn&#x27;t lend itself well to version control.</i><p>I&#x27;ll comment as someone who does hand-write and scan my notes. I date and number every page, then put a pile through a sheet-feeding scanner every so often. Sometimes I put date and page numbers in my code comments, so I can find my notes on where the code came from. I also enter a line of text (or more if necessary) about each scanned page so I can search that. Something I do in a brain-dead moment every month or two. It can be interesting to look back through the notes and see if I&#x27;ve forgotten about anything interesting.<p>Often I&#x27;ll write out the math for something multiple times before I really understand it, and using a pen works much better for me. Only a small fraction of what I write out is worth TeXing up.