On the progress page, we use green, yellow and red dots to indicate the priority of the languages you need to practice, based on timing intervals to enhance your memory.
The green light indicates that you have finished your session in the last 24 hours. Languages with green dots will go to the end of your list.
The yellow dot means that you haven't practiced the language for more than 24 hours and this is becoming a high priority.
The red dot means that it's been too long since you've practiced. Your memory and progress is slipping away and you need to get back on track now! If you don't intend to continue with this language, you can hide it from the list.