What Is a Brain

Overview

A brain is your personal knowledge space — a self-contained network of thoughts and the links between them. Where other tools put information into folders and files, a brain lets ideas connect the way your mind actually works: visually and without a fixed hierarchy. The network you navigate, the Plex, is the visual map of one brain (see The Plex).

You can have many brains, and each is independent. People often keep separate brains for separate worlds — one for work, one for a research project, one for personal life — so the ideas in each stay together without mixing.

What a Brain Contains

A brain holds:

A brain window: the title bar and the toolbar along the top, the Plex on the left with the thought Launch Plans active and its parents, children and jumps around it, and the content area on the right showing its note

Thoughts — the ideas, things, and topics you track, each with a name, note, and attachments.
Links — the parent, child, and jump connections between thoughts that give the network its shape.
Types and tags — thoughts that classify and label other thoughts.

Everything you do in TheBrain happens inside a brain, and brains are listed and opened from the brains list (see The Brains List).

A brain can stay entirely local on your device or sync to the cloud so it's available across your devices — see Syncing Brains.
Starting a brand-new brain is quick — see Creating a Brain.