Study material
Short revision notes on the topics that decide marks — written to be read in one sitting, not skimmed for an hour.

Notes are for understanding a topic the first time. They are not revision — revision is answering questions and finding out what you forgot.
Every note is written to be finished in one go. If you are skimming, the topic is too big and needs splitting.
A definition you can look up. What matters is seeing the method applied to a question that looks like your exam.
Reading a note and answering ten questions on it are different skills. Only the second one is examined.
“You do not forget a topic because you never learnt it. You forget it because you never tested it.”