Jasmine Flowers come from the jasmine tree, usually Arabian jasmine, Jasminium sambac. Jasmine flowers are pretty white flowers.
Fresh jasmine flowers have a strong, fresh floral aroma, but this fades on drying. So fresh jasmine flowers are used to infuse the flavour into green tea and white teas to make jasmine tea. Most jasmine teas on the market however are , also, flavoured with jasmine flavouring to perk up the smell. Try and avoid these ones if possible.
Dried jasmine flowers are a pretty decoration for jellies and salads, but they imbue these with no aroma or flavour.