The study of fungi. Fungi make up their own biological kingdom, alongside plants and animals. Mushrooms are the fruiting body of saprophytic fungi. Therefore, all mushrooms are fungi but not all fungi are mushrooms. Fungi breathe oxygen and expel carbon dioxide like animals and microbes. It is a common misconception that mushrooms are similar to plants--recent scientific literature has revealed that fungi are much more similar to animal cells than we had previously believed!
A spore is a single reproductive cell of fungi, requiring another compatible (+/-) spore to germinate to mycelium. Spores are produced underneath the gills of the mushroom caps and dispersed when the mushroom reaches maturity.
Mycelium can be thought of as mushroom roots. Two compatible spores (+/-) combine to form mycelium, which form hyphae, which expand to create mycelial networks. Mycelium are fiber-like strands of fungal cells that consume a nutrient source known as a substrate. Mushrooms will grow from the saprophytic mycelium.
Spawn is created when the living fungal roots, called mycelium, spread throughout a substrate, such as oats or sawdust. Once the mycelium has spread throughout its nutrient source, creating spawn, mushroom fruiting can be triggered. Spawn is commercial tactic used to cultivate mushrooms in high quantities.
The nutrients source for a fungus, such as hardwood sawdust, oats, straw, logs, etc.
How long it takes mycelium to work its way through a substrate e.g., a fruiting block. Once the mycelium has worked its way through the entirety of a substrate, we refer to the spawn as colonized. Once colonized, the mushrooms are ready to fruit.
The process of expanding biological material in a larger substrate e.g., putting a piece of agar in sterilized grain or putting grain spawn into a monotub.
Spawn is created in a sterile environment, which means free of bacteria, mould, and other living microorganisms that could compete with your mycelium for nutrients. When substrates are not sterile (contaminated)--especially nutrient dense substrates such as whole grains--it is nearly impossible to create spawn due to competition from other moulds and bacteria in the air that flock to the substrate.