Connect 4 Glossary
Short, plain definitions of the words you will meet in Connect 4 guides and in this game's menus.
- Column
- One of the 7 vertical lanes of the board. You choose a column, never a row: gravity decides where the disc lands.
- Row
- One of the 6 horizontal levels, counted from the bottom (row 1) to the top (row 6).
- Disc
- A playing piece. Each side has 21 discs: red and yellow.
- Gravity drop
- A disc always falls to the lowest empty slot of the chosen column.
- Four in a row
- The winning pattern: four discs of one colour in a straight line, horizontally, vertically or diagonally.
- Center column
- The fourth column. It belongs to more possible fours than any other column, so it is the most valuable one to control.
- Threat
- An empty slot where one player would complete four in a row if they could drop a disc there.
- Open three
- Three discs in a line with an empty slot at an end that can already be played. It must be blocked at once.
- Block
- Placing your own disc in the slot your opponent needs to finish four.
- Double threat (fork)
- A move that creates two threats at once. The opponent can block only one, so the other wins.
- Odd and even threats
- A threat on an odd row (1, 3, 5) normally favours the first player, one on an even row (2, 4, 6) the second player.
- Zugzwang
- A position where any move you make helps your opponent, for example because it lets them drop onto the slot above yours and win.
- Tempo
- Who is forced to move next when safe moves run out. Winning the tempo battle often decides the endgame.
- Draw
- All 42 slots are filled and nobody has four in a row.
- Daily puzzle
- A fixed opening of eight moves chosen from the date, the same for everybody that day. You take over the side to move and play it out.
- Alpha-beta search
- The look-ahead method used by the computer opponent: it tries moves several turns deep and skips branches that cannot change the result.
- Replay
- After a game ends you can step back and forward through every move to see where it was decided.
Ready to try these ideas? Read creating double threats and blocking your opponent, or return to the full rules.