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How to play Drop7
Drop a disc, match its number, and make room for the next row. See the rules in motion.
Learn the rules
Learn the game
Learn the rules, explore the ideas behind a good move, and find clear definitions of the game's vocabulary.
Concepts
Visual lessons on choosing moves, making room on the board, and understanding how strategies learn. Explore any topic that interests you.
- Lesson 01
Choice and chance
You choose where a disc lands. The game chooses what comes next. See how both shape a good move.
Explore the concept - Lesson 02
Evaluating a board
How a player estimates the value of the board it leaves behind.
Explore the concept - Lesson 03
Score and survival
Why clearing space helps you survive the rising board and keep earning points.
Explore the concept - Lesson 04
Reading a score
How unusually long games affect an average, and how to compare strategies fairly.
Explore the concept - Lesson 05
Ranking the seven columns
Why choosing a good move means comparing all the available columns.
Explore the concept - Lesson 06
Oracles and teachers
How a program with hidden information can help teach a player that only sees the board.
Explore the concept - Lesson 07
What more compute buys
What changes when a player looks further ahead, considers more futures, or spends longer learning.
Explore the concept - Lesson 08
Learning from play
How played games become examples that help a program choose its next move.
Explore the concept
Vocabulary
Short definitions grouped by topic. Each term has its own link, so you can return to it as you read.
Game mechanics
Discs, clears, chains, and the rising board.
Browse definitionsSearch and decisions
Choices, chance, and looking ahead before a move.
Browse definitionsLearning and training
Policies, teachers, and learning from played games.
Browse definitionsEvidence and results
Game samples, comparisons, and the labels on a result.
Browse definitions
Techniques
Explore the methods used to build a player, with worked examples and links to the strategies that use them.
Expectimax search
When some of what happens next is your choice and some is luck, look ahead by taking the best of your options and the average of luck's.
Read the primerHeuristic evaluation
When the search has to stop before the game ends, a hand-written formula guesses how good the board it stopped at is.
Read the primerQ-learning and value learning
Keep a number for 'how good is it to do this here', play, and after each step nudge that number toward what actually happened plus the best number available next.
Read the primerN-tuple networks
Look at the board through many small windows, look each window's contents up in a table of learned numbers, and add the numbers.
Read the primer
Leaderboard guides
How scripted rounds work and how a program sends its moves. The leaderboard is a playground; its totals are not research evidence.
The methodology and research records are in Docs. You can also follow the work in the research log.