Matcha is a special kind of green tea from Japan, mainly used in formal ceremonies. In the minds of most Japanese, matcha is linked to the tea ceremony.
Matcha neither looks like nor tastes like other kinds of tea. It looks like electric green cocoa, and has the mouthfeel of a well-made espresso. It tastes like baby green vegetables that might have been cooked by Ferran Adria or someone else into molecular gastronomy : perhaps blended microgreens, straight-up chlorophyll, young bamboo, and raw sugar.
We like to serve it in small cups, like espresso. When matcha is removed from its Japanese context, there is no need to replicate exact Japanese conditions of teamaking. One needn't wear a kimono, it need not be served on tatami mats, and one certainly doesn't have to study matcha for years on end to enjoy it. You could make it anywhere: at the breakfast table, at the office, at the yoga studio, on a hike (really!), or even in your car, especially if you've had a glass of wine or two.
Great matcha has many distinguishing features, but the top four are probably 1) Form of tea leaves. Unlike all other teas, including green teas, matcha is finely ground; 2) No steeping. Matcha isn’t steeped, it’s “eaten.” You simply pour hot water over the powder, froth it (either with a special handheld bamboo whisk or an electric milk frother), and drink the thick tea; 3) Off-the-charts health properties. Matcha is full of naturally occurring antioxidants and amino acids, roughly 20 times those of regular green tea; and 4)It’s A LOT like really good wine. Terroir (conditions in which it’s grown) is massively important -- it should have a balanced acid structure, a very long finish, and be full of umami. It should also froth up to a very fine crema, similar to espresso.