The dictionary offers two definitions of the word tea. One is an infusion in hot water of the leaves of Camellia sinensis , the plant which give us our common black and green teas. The second definition of tea is an unfusion in hot water of the flowers, leaves, or stems of any plant. Examples of such teas include camomile, mint, or linden.
Brazilians do not drink much tea (in the first sense of the word). But as I have been discussing in the past few posts (click here or here) they do drink enormous quantities of mate, derived from the plant erva-mate. In southern regions, it's mostly drunk in the form of the traditional chimarrão. In all parts of Brazil, however, people drink something which they call chá mate. Chá is the Portuguese word for tea, and so chá mate merely means mate tea. The difference between chimarrão and chá mate is that in chimarrão the leaves of the plant are dried, but are still green, whereas in chá mate, they are toasted. You can think of it as being the same as the distinction between green tea and black tea.
Chá mate can be bought in supermarkets in bulk or in tea bags, and can be used to make a hot drink like a "good cup of tea." In Brazil's tropical climate, however, the appeal of hot tea is considerably lessened, and a good portion of the consumed in Brazil is drunk in the form of iced tea, either home-made, or purchased in the form of pre-made, pre-sweetened, and often flavored iced drinks. It's a very refreshing however it's made, and makes a great thirst quencher at the beach, or in the hot sun. The commercial product, in line with Brazilian preference, tends to be very sweet, and so if you prefer a less-sweet drink, it's best to make it yourself, and keep some in the refrigerator at home.
Toasting the leaves of erva-mate do not seem to interfere with it's healthful qualities. Studies at the University of Santa Catarina indicate the the cholesterol-lowering properties of erva-mate are not reduced by toasting, and that drinking chá mate is equally beneficial in this regard as drinking chimarrão.