What is hash?
Hash is made by compressing kief using heat. Kief in simple terms is the sticky substance that covers the cannabis flower. The result of compression is a dry-paste-like block of high concentrate cannabis. You can smoke it by mixing it with tobacco, vape it in the form of oil or use it in your dab rig. Decarboxylated hash can also be consumed orally.
Cannabinoid Receptors. Why would you care about them?
Cannabinoid Receptors are antennas located in each human and animal cell. They pick up signals and transmit them to the nerves. The existence of cannabinoid receptors in the brain was discovered from in vitro studies in the 1980s.