Fruit salads are a great healthy dessert. They are a cold mixture of cut up fruit, instead of vegetables. They all come from plants. These salads just use sweeter parts of the plant. Like other salads, fruit salads use a dressing.
While most salad dressings are an oil and vinegar mixture, fruit salad dressings are a blend of sweet and sour flavours, but may be thickened with oil or egg.
Many fruit salads are covered with gelatin. The resulting salad can be cut into slices and served cold. Moulded gelatin salads are made with either fruit or vegetables. Of course, fruit salads are popular desserts and vegetable salads are savoury dishes.
Occasionally people think that these gelatin salads are or can be vegetarian. However this claim is impossible. Gelatine is an animal product. It is made of collagen extracted from animal parts such as skin, bones and connective tissue.
Sometimes the fruit salad can be served in the rind (hard skin) of a large fruit such as melons. The melon is cut into balls with a spoon and mixed with other cut fruit. In such cases the dressing might only be a mixture of the juices of the different fruits, with a little sugar or lemon juice to balance the flavour.
Let us look at the history of these two words. The word fruit came into colonial English from Norman French in the late 12th century. The word gelatin, and the technology, is also from France, but is a 19th century import and does not date from the time England was a Norman French colony. France is England's neighbour across the English Channel and the French language has a long history of influence on English, especially in cookery and catering:- café, restaurant, hotel, cuisine, mousse, soufflé etc. The words fruit and gelatine give us a window on that history.
To summarise, a fruit salad is
A cold mixture of cut up fruit covered with a dressing.
As with garden and vegetable salads, fruit salads are cold mixtures with a dressing. Gelatin salads are different in that the final product is one large piece and not many pieces mixed together.