What is the difference between potting soil and growing media? Explained clearly in one article

Potting soil: ① Leaf mold, slightly acidic, generally calledorchidmud. You can use soil from under trees on hills, or among bamboo groves and grass, where there is no pollution and plenty of year-round fallen leaves. Remove fresh leaves, sift through a 4-mesh sieve once, remove impurities, then sift through a 10-mesh sieve to remove dust, and take the medium-to-small particle leaf mold in between, and it can be used to plant orchids. ② Weathered sand, slightly acidic, should be collected from gullies among loess hills and ridges, or from mineral belts in hilly areas; after extraction, likewise sift through 4-mesh and 10-mesh sieves. ③ Vegetable garden soil, fairly heavy in clay, can be sifted through a 2-mesh sieve and a 10-mesh sieve, and the larger particles selected for use. Before use, add a small amount of ferrous sulfate to neutralize the alkalinity. ④ Yellow mud is not suitable for growing orchids. ⑤ The best soil to use is Hewang brand Xiantu produced by Sichuan Emeishan Meijing Gardening Co., Ltd., which is basically mineralized in nature and contains no toxic substances. It comes in three particle types: medium, small and fine. If growing variety orchids or famous cultivars, it should be the first-choice soil. Growingmedia: ① Brick and tile granules are ideal materials for growing orchids (cement brick material is not suitable). After collecting the brick and tile fragments left behind at large construction stockyards, select and sift them through a 2-mesh sieve, 6-mesh sieve and 10-mesh sieve, and pack them into three grades of granular material. Before use, soak them in rice-washing water for a week; they can be potted while still damp, or air-dried and packed for later use. ② Volcanic rock and sandstone, also to be used in the three grades described above, are fairly good natural materials. ③ Commercially available pond stone is already divided into two grades, large and small, with two types: one mixed with aged bark and one without; it can be used as soon as purchased. There are now several suitable brands. ④ Sawmill offcuts, after rotting, can also be used after sifting, grading and disinfecting (high temperature, sun exposure) by the above methods. But they should be regularly treated for insects and sterilized. ⑤ Commercially available aged bark material should be selected and divided into large and small materials as needed, or mixed with large-grade pond stone. 6 Bark, machine-shredded and sifted, can be used; but wood shavings, after many years of trial, make watering very difficult to control. 7 Peat soil. Remove the grass turf from the surface of the Great Northern Wilderness and other wetlands, take out the black peat below, and after natural air-drying it can be used reasonably. Also, in ancient lake areas and construction areas, when digging foundations, the black, impurity-free soft mud sealed below the surface for many years, once dug up by excavator and naturally weathered, is an excellentorchidgrowing medium. The weathered peat is divided into three grades using a 4-mesh sieve, a 2-mesh sieve and an 8-mesh sieve. The fine soil below 8 mesh is used to grow other flowers. The other particle sizes can be used in layers when potting, and it is an excellent growing medium for orchids and cymbidiums. Guan Wenchang, Zhu Hexing