TwixT is a two-player abstract strategy board game invented by Alex Randolph. It is a member of the connection game family, along with games such as Hex, Havannah, Y, and *Star.

Twixt is played on board with a 24×24 grid of holes, with the four corners missing. The two players are Red and Black; the topmost and bottommost rows belong to Red, and the leftmost and rightmost rows belong to Black. (Different sets may use different colors.)

The rules are as follows:

The players take turns placing pegs of their respective colors on the board, one peg per turn. 
A player may not place a peg on the rows which belong to his or her opponent. 
Red places the first peg. To counteract first-move advantage, the pie rule is suggested. (One-move equalization is part and parcel of the original rules as written by Randolph, but some sets sold in the US did not mention it.) 
After placing a peg, you may link one or more pairs of pegs on the board which are all your own colour. The links can only go between two pegs a knight's move away from each other, and cannot cross another link; they block other links, most importantly the opponent's. You may remove your own links (but not your opponent's) in order to rearrange the sequence of links on the board. 
The first player to make a continuous chain of linked pieces connecting their two sides wins. If neither side can achieve this, the game is a draw. 
3M originally published TwixT as part of its Bookshelf Games line; Avalon Hill took over publication at a later date. It is no longer produced in the United States of America, although Schmidt Spiele produced copies of the game in Germany, and Kosmos published a version of the game in 1998.