Distinguishing cannabis and hemp can be confusing, so let's make it simple. There are many varietals of Cannabis sativa, all of which have different amounts of THC and CBD. Cannabis sativa varietals that have more than 0.3 percent THC are commonly referred to as marijuana. Hemp is any varietal of Cannabis sativa that contains less than 0.3 percent THC.
Cannabis for industrial uses is valuable in tens of thousands of commercial products, especially as fibre[107] ranging from paper, cordage, construction material and textiles in general, to clothing. Hemp is stronger and longer-lasting than cotton. It also is a useful source of foodstuffs (hemp milk, hemp seed, hemp oil) and biofuels. Hemp has been used by many civilizations, from China to Europe (and later North America) during the last 12,000 years.[107][108] In modern times novel applications and improvements have been explored with modest commercial success.[109][110]
His parents took him to more than 20 doctors around the country, and he tried more than a dozen medications. Nothing worked. Two years ago, the Leydens were at the end of their rope. They decided to see whether marijuana might help. (Medical use of the drug is legal in the District, where they live, and the Leydens found a doctor willing to work with them.) In 2014, Jackson got his first dose of cannabis.
Hashish (also spelled hasheesh, hashisha, or simply hash) is a concentrated resin cake or ball produced from pressed kief, the detached trichomes and fine material that falls off cannabis flowers and leaves.[178] or from scraping the resin from the surface of the plants and rolling it into balls. It varies in color from black to golden brown depending upon purity and variety of cultivar it was obtained from.[179] It can be consumed orally or smoked, and is also vaporised, or 'vaped'.[180] The term "rosin hash" refers to a high quality solventless product obtained through heat and pressure.[181]
The leaves have a peculiar and diagnostic venation pattern that enables persons poorly familiar with the plant to distinguish a cannabis leaf from unrelated species that have confusingly similar leaves (see illustration). As is common in serrated leaves, each serration has a central vein extending to its tip. However, the serration vein originates from lower down the central vein of the leaflet, typically opposite to the position of, not the first notch down, but the next notch. This means that on its way from the midrib of the leaflet to the point of the serration, the vein serving the tip of the serration passes close by the intervening notch. Sometimes the vein will actually pass tangent to the notch, but often it will pass by at a small distance, and when that happens a spur vein (occasionally a pair of such spur veins) branches off and joins the leaf margin at the deepest point of the notch. This venation pattern varies slightly among varieties, but in general it enables one to tell Cannabis leaves from superficially similar leaves without difficulty and without special equipment. Tiny samples of Cannabis plants also can be identified with precision by microscopic examination of leaf cells and similar features, but that requires special expertise and equipment.[12]
First of all, you need to know that CBD oil can come from both the hemp plant and from medical marijuana.  Both of those plants are different varieties of cannabis but they’re much different in the terms of chemical compounds they have.  Medical marijuana is good for people with certain ailments because it does contain the THC and it can contain any varying level of the THC or any varying level of CBD.