How this library works

Every chess site will analyze your game. Most will hand you a report with a number next to each move. Reading the report feels like progress, and the next week you make the same mistake in the same kind of position.

This library is built on one idea: you do not need another engine, you need to remember. So every page here does three things, in this order.

1. Name the mistake

Each article is about one thing that goes wrong in club games. Not “tactics” or “strategy”, but hanging a piece, dropping a pawn, walking into mate, throwing away a winning position. Those are the labels the engine attaches to moves on this site, and the articles use the same words on purpose. When a page says “this happened 28,000 times in our games”, it is the same tag that shows up in your own game review.

2. Show you how to see it a move early

Knowing what a fork is does not stop you from walking into one. What stops you is a habit: a question you ask before you move, and a shape you recognise on the board. Each article ends with a tell, the concrete thing to look for, and a habit, the thing to do about it. That is the part worth remembering.

3. Send you back to your own games

Reading is the cheapest part. At the bottom of each page there is a quiz, and on the right there is a button to repair: the site finds the positions from your own games where this exact mistake happened, puts you back in the position, and asks for the move you missed. Then it asks again in a few days. That is how a lesson stops being something you read and becomes something you do.

How to use the page you are on

• Mark as read at the top or bottom. Your progress shows in the menu on the left. You need an account for that, which takes an email and nothing else.
• Select any sentence to highlight it, add a private note, leave a comment for other readers, or ask the tutor about it.
• The tutor on the right knows the page you are reading and, if you have imported your games, the mistakes in your own repair queue. Ask it to explain a paragraph differently, to give another example, or to say how this applies to your games. It answers from the page and your data, not from thin air.
• The outline on the right follows you as you scroll. Use it to jump.
• The quiz is short and honest. Your best score is saved.

Who this is for

Players rated roughly 1000 to 2000. Below that, the fastest improvement is simply not leaving pieces to be taken, and the first tactics article covers it. Above that, you already know everything written here and your problem is doing it under pressure, which is what repair is for.

Where to start

If you have not imported your games yet, read Why you keep making the same mistake and then try it on your last games with no account. If your games are already here, start with the section that matches your most common tag on the patterns page. For most players that is hanging pieces.