The US government's public library of cybersecurity standards, guidance and publications, including the SP 800 series, project pages, news and events.
From the site: CSRC provides access to NIST's cybersecurity- and information security-related projects, publications, news and events.
Why I recommend it: Free and public, no account needed. This is the primary source behind most security "best practice" advice you will read elsewhere, so cite it directly rather than a blog summarising it.
Jake Taylor argues that public, standardized AI testing with formal reasoning checks is needed to close the widening "verification asymmetry" between AI capability and oversight.
Why I recommend it: If you want to work in AI governance or assurance, this is the vocabulary hiring managers use — verification, benchmarks, interpretability.