Obsidian (software)
Obsidian is a local-first Markdown note-taking application released in 2020 that stores notes as plain files on disk and links them with [[wikilink]] syntax and a built-in graph view.
Obsidian is a personal knowledge-management application released in beta in 2020 by Erica Xu and Shida Li (operating as Dynalist Inc.). It stores every note as a plain Markdown file in a user-chosen folder called a vault, which can be version-controlled, backed up, or synced through any external mechanism. Links between notes use the wiki-style Note Title syntax popularised by Roam Research and originally established by UseModWiki and MediaWiki; standard Markdown links are also supported, and the application maintains a backlinks panel and an interactive graph view for navigating the resulting network. Obsidian's core editor is free for personal use, with paid add-ons for end-to-end-encrypted sync and one-click publishing. A large community plugin ecosystem extends it with features such as Dataview (queryable metadata), Templater (templating), Canvas (spatial whiteboards), and many import/export bridges. The combination of local plain-text storage, bidirectional links, and plugin extensibility has made it one of the most widely used "tools for thought" alongside Logseq and Roam Research.