Tana

Tana is a next-generation note-taking and knowledge management tool built around the concept of supertags -- structured tags that turn any node in your notes into a typed object with defined fields, views, and behaviors. Combined with AI that understands your personal knowledge graph, Tana helps users build knowledge systems that can be queried, cross-referenced, and acted on in ways traditional notes cannot. Researchers, knowledge workers, and personal knowledge management enthusiasts use Tana to build comprehensive second brains that are more structured than Notion but more interconnected than linear documents. The supertag system lets users create custom databases for contacts, projects, books, meeting notes, and research sources that automatically link and cross-reference. AI commands run on any content in your workspace. Tana is positioned at the power user end of the PKM spectrum. Its learning curve is steeper than most note-taking apps, but users who invest in learning it describe significantly more leverage from their notes. It's particularly powerful for researchers and writers who accumulate large volumes of source material and need to find connections across it.