'Blitz' mode is a training mode that emphasizes speed, and is useful for seeing a large number of positions, which assists in learning tactical patterns, a very important part of improving tactical strength.

In Blitz mode, your rating adjustment is partly determined by how quickly you are able to solve problems.

'Standard' mode is a tactics training mode that allows you to take as much time as you like on each problem. Standard mode is suitable for calculation practice, and gives you a chance to see harder problems, that require more thought and deeper calculation than you will see in blitz mode.

In Standard mode, your rating adjustment is based only on whether you get the problem correct. Time taken is shown on the screen, and recorded in your results, however it is ignored for rating adjustment purposes.

The mixed rating type uses a hybrid standard/blitz rating adjustment, and includes both winning and non-winning (sometimes called "defensive") problems. Problem attempts are rated the same as standard mode if they are solved under 5 minutes, i.e. time will not be used as part of the rating adjustment, and only correct/incorrect matters. If the time exceeds that level, the problem is rated in a similar way to the blitz rating method, i.e. you start to get less reward for a correct solution if you take longer than the average solution time across all users.

The main differences between blitz and mixed mode after the 5 minute threshold has been reached is that there is no bonus for fast solving, there is no "time after first move" penalty, and the minimum average time you are measured against will be at least the no time-adjustment threshold of 5 minutes. This means for problems at your current rating you should be able to take at least 10 minutes before you start to lose rating points on a correct solution.