The document provides a brief history of computers, starting with the abacus over 5,000 years ago. It discusses the development of early mechanical adding devices, including Pascal's "Arithmetic Machine" in 1642 and Leibnitz's stepped reckoner in 1671, which could perform multiplication, division, and calculating square roots through repeated additions similarly to how digital computers operate. The document then defines an essay as an attempt to write one's own ideas, impressions, thoughts, or opinions on a given subject in a single prose piece. It provides tips for writing an essay, such as jotting down ideas and deciding on an introduction, main body, and conclusion.