Glossary
The vocabulary of personal knowledge management, defined in plain language: the methods, the building blocks, and the technology behind modern note systems.
A second brain is an external, digital system that stores and organizes the information you want to remember, including notes, articles, files, and ideas, so your mind is free for thinking instead of storage. The term was popularized by Tiago Forte, whose method treats the system as a trusted place you capture into daily and retrieve from when you need it.
How to build a second brain →Personal knowledge management is the practice of capturing, organizing, and retrieving the information an individual encounters, so it can be found and used later instead of being forgotten. PKM is the broader discipline that contains second brains, the Zettelkasten, PARA, and most other note-taking methods.
Personal knowledge base in Mindly →Cognitive offloading is the use of external tools, such as notes, lists, or software, to reduce the mental effort of remembering. Research on memory shows that people who store information externally tend to remember where it lives rather than what it says, which is why an offloading system you cannot search reliably fails you.
Why blind offloading fails →Capture is the act of getting information out of your head or your environment and into a trusted system at the moment you encounter it. Capture friction, meaning how many steps a save takes, is the strongest predictor of whether a note-taking system survives, because a system you hesitate to feed goes stale.
Quick capture in Mindly →A digital garden is a collection of evolving notes that are tended and revised over time like plants, rather than published once and finished like blog posts. Gardens sit between a private notebook and a public blog, and their entries are expected to grow, merge, and change as understanding deepens.
A Zettelkasten, German for slip box, is a note-taking method built on small atomic notes that are densely linked to one another, so trains of thought emerge from the connections between ideas. Sociologist Niklas Luhmann used the method to write more than seventy books, and it underlies most modern linked-notes software.
Zettelkasten method explained →PARA is an organizational framework that sorts all of your information into four categories by actionability: Projects, Areas, Resources, and Archive. Created by Tiago Forte, it answers the question of where a note should go by asking how soon you will act on it rather than what subject it belongs to.
PARA method explained →CODE is a four-step knowledge workflow standing for Capture, Organize, Distill, and Express, describing the path information takes from first encounter to finished work. It is the process half of Tiago Forte’s second brain method, with PARA as the structure half.
CODE method explained →Progressive summarization is a technique for distilling notes in layers: the captured text is the first layer, bolding the best passages is the second, highlighting the best of the bold is the third, and a summary in your own words is the fourth. Each layer is added opportunistically, when you actually revisit a note, so the most-used notes end up the most refined.
Progressive summarization explained →Evergreen notes are notes written and organized to evolve and accumulate across projects over years, in contrast to transient notes that serve one meeting or one task and are never read again. Articulated by Andy Matuschak, the practice asks for atomic, concept-oriented, densely linked notes with titles that read like claims.
Evergreen notes explained →Interstitial journaling is the practice of writing a brief timestamped note in the gaps between tasks, recording what you just finished and what you intend to do next. Introduced by Tony Stubblebine, it turns context switching into a moment of reflection and leaves a searchable trail of how your day actually went.
A Map of Content is a note that serves as a curated index of links to other notes on a topic, giving a link-based system structure without folders. MOCs act like trailheads: instead of one rigid hierarchy, any number of maps can organize the same notes for different purposes.
An atomic note is a note that contains exactly one idea, kept small enough to be linked, referenced, and reused independently of where it first appeared. Atomicity is what makes linked note systems work, because a note about one thing can connect cleanly to other notes in ways a long mixed document cannot.
A backlink is a reference showing which other notes link to the note you are currently reading, making connections visible from both ends. Bidirectional linking, popularized by Roam Research and now standard in linked-notes tools, lets a web of ideas form without a predefined hierarchy.
A knowledge graph is a network representation of information in which ideas or notes are nodes and the relationships between them are edges. In personal knowledge management, the knowledge graph is the map of how everything you have saved connects, and it is increasingly built by software automatically rather than drawn by hand.
The Mindly mind map →A mind map is a visual diagram that lays ideas out as connected nodes, so the relationships between them can be seen and explored rather than remembered. Mind maps are used both for brainstorming from a central idea and, in modern tools, as a navigable view of an existing library of notes.
Explore the mind map →Spaced repetition is a memory technique in which material is reviewed at increasing intervals, timed to arrive just before you would otherwise forget it. It exploits the spacing effect, one of the most replicated findings in memory research, and it is the engine behind flashcard systems like Anki.
Semantic search is search that matches the meaning of a query rather than its exact words, so a search for the pasta you cook in one pan can find a note titled one-pot spaghetti. It works by comparing embeddings, numerical representations of meaning, instead of keywords, which is why it finds things you cannot name precisely.
Semantic search in Mindly →OCR is technology that reads the text inside images, scans, and photographed pages, turning pictures of words into searchable text. In a note system, OCR is what makes screenshots, whiteboard photos, and scanned documents findable instead of lost in an image library.
Searchable screenshots →AI auto-organization is the use of artificial intelligence to read saved content and apply tags, summaries, and links automatically, replacing the manual filing that most note systems require. It shifts organization from a discipline the user maintains to a property of the software, so structure emerges from the content itself.
How AI organization works →A web clipper is a tool that saves web content, whether a full article, a selection, or a link, into your note system, so what you read online becomes part of what you can search later. Good clippers preserve the content itself rather than just the address, which protects your library from pages that change or disappear.
Web clipping on a Mac →Read-it-later apps queue articles and links you encounter during the day so you can read them at a better moment, in a clean, distraction-free format. The category was defined by Instapaper and Pocket, and its core challenge is that unread queues grow faster than reading time, which is why modern tools pair saving with summaries and search.
A read-it-later that organizes itself →Local-first software keeps your data on your own device as the primary copy, rather than on a vendor’s server with your device as a mirror. For a knowledge library, local-first means the notes remain yours and readable regardless of any subscription, outage, or company decision, which matters for a system meant to last decades.
Private, local notes on a Mac →Mindly does the organizing, linking, and finding automatically. Free for macOS, no account required.