Course
How the feed decides what you see
Work out who pays for a free app, how every post is scored for you, why the feed narrows, and who holds the dial.
The shape of it
13 lessons
About 59 minutes in total. Your progress is kept on this device — no account, nothing sent anywhere.
Course complete
Put your name on it and print it, or save it as a PDF. Nothing is sent anywhere.
The lessons
Free, and paid for
3 lessons · about 14 min01The app is free, and someone pays
Work out who the customer of a free app really is.
About 5 min
02Time is the score
Tell apart what the app can count from what it cannot see.
About 5 min
03A moment of you, sold in an auction
Trace how a gap in your feed is sold in the instant it loads, and what sets the price.
About 5 min
The ranking machine
4 lessons · about 18 min04The feed is a sorted list
Spot the difference between getting onto the list and getting up it.
About 5 min
05The score is a guess about you
Work out a post's score from a guess and a weight, and say which of the two is about you.
About 5 min
06It learns from what you do, not what you say
Spot which of your actions the app hears loudest.
About 5 min
07The loop
Trace how what you are shown changes what you do, and back again, until the feed narrows.
About 5 min
What rises
3 lessons · about 14 min08Strong feelings travel faster
Work out why a post that makes people react climbs the list, whatever it is about.
About 5 min
09The makers follow the score
Trace how a weight inside the company changes what creators make.
About 5 min
10The buzz that brings you back
Tell apart the app reaching out to you from you reaching for the app.
About 5 min
The hands on the dial
3 lessons · about 14 min11The test that runs on you
Say what an A/B test can find out, and what it can never ask.
About 5 min
12The dial the company holds
Work out what one changed weight does to a billion feeds, and who can see it move.
About 5 min
13Taking a feed headline apart
Spot which of the course's six parts a real headline is about.
About 5 min