Opening sequences prepared and memorized in advance are called book lines (book openings), and a collection of them is an opening book. If you have only just started Othello, you do not need to spend much time memorizing book lines. Engine analysis shows that the opening has a great many roughly equal paths, and even moves that look bad often lose little. At first, playing a lot helps far more than memorizing.
Engine analysis suggests that with perfect play by both sides the game ends in a draw. Neither color is at a disadvantage from the start, so play Black and White evenly. Sticking to one color reduces your chances to learn the other color's openings.
As you improve: make book lines your own
The stronger your opponents, the more your prepared lines matter. Memorizing sequences alone does not make them yours. Understand the meaning of each move, and also study how to play when the opponent leaves the book line.
- Start from your own games: record the games you play and use FlipSight analysis to find and fix the moves that cost you in the opening. Adding one move at a time this way builds your own opening book.
- Choose only what you need: preparing every answer to every reply makes the amount to memorize grow exponentially. Start with the branches you meet often, and write down only the lines you will actually use.
- Separate research notes from a practical summary: keep everything you investigate in research notes, and memorize only a short per-color summary of the lines you will use in games.
Which lines to choose
Choosing only the theoretically best move is not always the answer. In games between people, a difference of two or three discs is small, and the side that makes fewer mistakes wins. So consider the following as well.
- Branches the opponent has seen less: if the theory is about equal, a less common move the opponent may not know works better in practice. Statistics in FlipSight analysis (the More ⋮ menu) shows how often each position was reached and the Black and White win rates in tournament and online games, so you can tell common moves from less common ones.
- Branches where you memorize little and the opponent memorizes a lot: if the win rates are similar, choose the line with less to memorize. The Umigame Number in FlipSight analysis (the turtle icon in the More ⋮ menu) shows, for each candidate move, how many lines Black and White must memorize to play best to the end. Choose a move with a low value for your side and a high value for the opponent.
- Avoid branches that are too bad: even if a move is less common, if the engine prediction is worse than -4 it is hard to recover even after the opponent makes one or two mistakes.
Using the Opening Dictionary
The FlipSight Opening Dictionary has the sequences, boards and engine evaluations of about 650 named openings, plus bars showing Black wins, draws and White wins in the tournament games that passed through each opening. You can also filter by Black or White win rate. The engine evaluation predicts best play by both sides, while the tournament win rate is what people actually played, so the two can differ. Looking at both helps you tell theoretically good moves from moves that work well in practice.