Though your question is a bit vague, it sounds like you are looking for ideas for an essay about how machines have affected man's life. I will give you a couple ideas to think about. First, though you clearly must include some factual evidence, you could write a personal essay and talk about how machines have affect your life. You could, for example, compare and contrast the speed of information in your life to a grandparent's life. Or, you could simply write about how your life would be different without things like technology, cars, planes, or microwaves.
In another direction, you could leave yourself out of this essay completely and write about the historical progression of machines from their beginning to where we are today. Follow the link provided below to see a list of how machines are classified. In order to keep this essay as focused as possible, I would probably choose only one type of machine from the list and go into detail about it.