Saved on this device
Follow your curiosity
What discovery has been shared with you?
FACTREE gives you something interesting to discover every day — and something worth talking about together.
Start with one fact. Explore it, go deeper, then follow whichever branch catches your imagination.
Choose subjects for a surprise
Exploring any topic
Begin your discovery
Choose one or more subjects above, or leave Any Topic selected and let curiosity decide.
Mathematics
Quick fact
A topological sort exists for a directed graph if and only if the graph has no directed cycles—such graphs are called directed acyclic graphs (DAGs). This linear ordering respects every edge direction, making it essential for scheduling tasks with prerequisites.
Why this is interesting
You need to take a set of courses, but some depend on others. How do you find a valid order to take them all?
Continue with your current subject selection?
A little curiosity, delivered
Receive the title, Quick Fact and Why this is interesting. If it catches you, open it to continue your current FACTREE journey and explore the rest.
Email delivery is currently in private preview.
Email preferences
Confirm below and FACTREE will stop sending your subscribed facts immediately.
Email preferences updated
You will no longer receive FACTREE facts at .
Subjects · study & training · careers
Choose something you are considering. FACTREE will give you a clear picture of what it contains, how its main parts connect and where it could lead.
This private catalogue connects 31 subjects, study routes and careers across six broad areas. Public Maps and learner routes remain off.
Browse subjects
Open a subject to see its complete shape at a glance. You can always return here and choose something else.
See what programming involves, how its main areas connect, and whether you find the knowledge interesting enough to take it further.
Structuring the Programming Map…
Complete subject map
Move from the one-screen overview into all 19 areas. Open any area, compare possible Paths and return to the overview whenever you want.
Loading the complete Programming Map…
Curiosity quiz
One question at a time. A wrong answer is simply another way into something worth knowing.
Administrator
Review learner demand, card visibility and private knowledge-architecture evidence.
Knowledge architecture
This background view organises existing cards. It is separate from the authored lessons above.
Review public suggestions and repeated searches. Approval alone does not add generator tasks.
Hide a published card reversibly, then optionally queue it for a reviewed merge or permanent retirement.
Curriculum coverage
Discovery cards in this subject
