A Second Brain can be thought of as your personal assistant, but better. It is a versatile tool that combines the functions of a study notebook, personal journal, and sketchbook for new ideas. With perfect memory and the ability to scale to any size, it is always on and can adapt to your changing needs over time. By delegating tasks of capturing, organizing, and distilling information to technology, you can free up time and energy for self-expression.
A Second Brain is also known by other names such as Personal cloud, field notes, external brain, extended mind, digital archive, digital garden, digital commonplace book, Zettelkasten (meaning “slip box” in German, coined by influential sociologist Niklas Luhmann), and Memex (a word invented by American inventor Vannevar Bush).