Growing cannabis indoors mean replacing the earth the plants live in their natural environment, to something that you will keep in your grow area. Though pot filled in earth is the most obvious choice, the possibilities are virtually endless.
The starting point for every beginner and the most popular choice is a simple pot. Usually plastic, with drainage holes at the bottom, these come in a wide range of sizes, starting from the 0,1 liter seedling pots to huge 30+ l ones for LST and similar growing techniques. To collect the overflowing water, using saucers or growing tables is a good idea. Though water is a good friend of plants, it is not necessarily so with electricity.
Growing trays allow you to water your plants from the bottom - filling the tray instead of each pot separately. Such manner of providing the plant its nutrients fosters root development, as the plant has to strive for the feed by quickly going deep down to the very bottom of the pot.
In automated watering setups and hydroponics systems, all kinds of irrigation hoses and reservoirs will also be needed, to store and distribute the nutritional solution.