For the rules of Lines of Action, see GameHelpLinesOfAction
Read more about history, strategy and tactics at https://boardspace.net/loa/.
The game can become quite tactical in open positions where the checkers on both sides are mobile. The strategic depth of the game, however, derives to a large extent from blocking strategies designed to limit the opponent's mobility. It can be advantageous to pin one or more enemy checkers against the side of board by moving in the second row or column.
Having more checkers is usually an advantage, because they can limit the opponent's options as they mass together. On the other hand, material considerations are not all-important, because having fewer checkers also means having fewer to unite.
'Black' refers to the dark (red) pieces.
Black plays b1-b3.
This move gives White no opportunity to capture, and threatens to hem in the pieces on the a-file.
White moves h4-f2.
White threatens the mobility of Black's checkers in the bottom row.
Black plays d1:a4.
It isn't clear whether the capture is advantageous or not. Black does now have an extra checker, but the move didn't do much to block White or build a central mass for Black. Usually early captures on the edge are not especially powerful, whereas early captures in the centre are extremely good.
White plays h2-e2, continuing the blockade of the first rank.
White, despite the substantial disadvantage of moving second, apparently is in the lead now due to the reduced mobility of Black's first-row checkers. White will soon play a2-d2, continuing to build his own bridge and forcing Black's checker on e1 to move sideways if it wants to join the game. It hardly helps for Black to try to escape with e1-c3, because that allows White to capture with a5:c3.