In English, a banana is a banana and a plantain is a plantain. But it's not surprising that you are confused about bananas in South America, where you'll find different words are used, depending on the country or region in which you live or are traveling.
For example, in most Central and South American countries plantains (cooking bananas) are plátanos (or plátanos de freir - frying bananas). But different terms are used to describe the sweet bananas that we eat. In Ecuador, bananas are guineos
and really small bananas are oritos
. In Nicaragua bananas are bananos
. In Venezuela the word for a banana is cambur
and in some countries (such as Argentina, Paraguay, and Uruguay) bananas are simply bananas
While in Bolivia a plantain is also a plátano
, just as it is in most other places, a banana is a plátano postre
(dessert banana) just because it's sweet, not because we only eat them for dessert.
Bananas are sweet and in Bolivia we eat them raw, on cereal or oatmeal, in fruit salads, milkshakes, banana cream pies and in desserts, muffins or banana bread, banana custard or pudding... the sweet delicious possibilities are endless.
Plantains, on the other hand, are a larger, longer, starchy variety of banana that is hard and flavorless and cannot be eaten raw. Plantains can be fried, baked in the peel, boiled (in soups), mashed, and even made into chicha (a fermented, alcoholic beverage). But there are two stages to plantains that determine how a plantain will be cooked. Green plantains.
When still green, plantains are used for cooking savory or salty meals. For example, green plantains are sometimes sliced lengthwise (just once to open them), stuffed with meat or cheese, and baked in the peel until they soften and the peeling turns black. It's a delicious dish called plátano relleno
(stuffed bananas). Plantains are also used to make salty "banana chips". Yellow plantains.
Once plantains turn yellow and ripen, however, they become sweeter. They still cannot be eaten raw because they are so hard and starchy, but when baked or fried they soften and become sweet and sticky, exuding a sort of honey-like substance that coats them. Sweet, sliced plantains fried in oil are a very common side dish to many meals in Bolivia. Sweet plantains are also used to make sweet "banana chips".
It takes time to become familiar with all the different varieties of bananas, because there are many. Even pink, purple and red ones!