流程图、思维脑图、UML 等，让思维快速呈现

思维导图

百度脑图 - 便捷的思维工具 (baidu.com)

思绪思维导图 (wanglin2.github.io)（源码）

markmap：使用思维导图可视化您的Markdown(Github)

xmind 图库

Freeplane - a free and open source software application that supports thinking, sharing information, getting things done at work, in school and at home.

图表（Diagram）

draw.io（桌面版）（Github）

Mermaid | Diagramming and charting tool

markmanx/isoflow：An open-source React component for drawing network diagrams.

Mermaid | Diagramming and charting tool

Online text to diagram tools | XOSH.ORG

D2 is a modern diagram scripting language that turns text to diagrams.（Github）

Systemizer - A system design tool (honzaap.github.io)

白板

Tldraw：a very good whiteboard （源码）

excalidraw/excalidraw: Virtual whiteboard for sketching hand-drawn like diagrams（网站）

susam/muboard: Self-rendering and distributable mathematics chalkboards (github.com)数学白板工具：Muboard，可通过编写 Markdown + LaTeX，在 Web 页面上进行展示，方便用于教学、演讲、会议等场景.

mbrlabs/Lorien: Infinite canvas drawing/whiteboarding app for Windows, Linux and macOS. Made with Godot. (github.com)

OpenBoard, the best interactive whiteboard for schools and universities

perfect-freehand - Draw perfect pressure-sensitive freehand lines.)（Github）

untools：更好思考问题的工具
https://untools.co/
收集了各种思维工具和框架，可以帮助我们更好地理解问题、分析、决策，包括有常用的金字塔、SWOT 分析、因果图、二阶思维等，类似于选择不同的思维模型来解决不同的问题。

免费作图工具 (yuque.com)