Hallo Mehrdad, i hope, that i can help you. "Speise" includes nearly everything, no specific food. But its also kind of a oldfashioned word, i don't remember the last time i used it. I will give you some examples, but mention that my english is not that good: Welche Speisen habt Ihr anzubieten? - Which food do you offer? (as a question in a restaurant) Was wollt ihr speisen? - What do you want to eat? (speise is written without capital so it is a verb) Mahlzeit is something more like a deep integrated food happening with your family or at work in your everyday life. "Mahlzeit!" is a common exclamation to celebrate the pause at work when they eat together. So that is just my short knowledge and i hope that i could help Aljoscha