Information that I need right now, but won't need once the task I'm working on is complete (e.g. A standard algorithm that I'm adapting to a specific use case). This information is normally in the form of a web page and will live in a tab in my browser. At the end of the day I close my browser, if I haven't finished the task I'm working on then I can pull that tab out of my browser's history the next day.
Information that my team needs (e.g. "this is how we run our Ansible playbooks"). This written up in a form targeting our environment and goes in our team's documentation (which is just a git repository full of markdown files).
Information that I will need access to regularly (e.g. Configuration options for one of the systems that we look after). This is also usually in the form of a web page and I'll simply add it as a bookmark to my browser (sometimes this also gets added as a link to our team documentation)
Information that I don't currently need but I'm trying to gain an understanding of (e.g. the contents of a book that I'm reading to expand my knowledge on an area). For this sort of information I like to have it in a form that I know will be around so that I can go back to it when needed - I'm usually pretty good at remembering the bigger picture from a book, which is enough for me to know where I need to go to look for the fine details.