When you write a business document, you must assume that your audience has limited time in which to read it and is likely to skim. Your readers have an interest in what you say insofar as it affects their working world. They want to know the “bottom line”: the point you are making about a situation or problem and how they should respond.
To save your reader time and to call attention to your strengths as a candidate, state your objective directly at the beginning of the letter. Example: I am seeking a position as a manager in your Data Center. In such a management position, I can use my master’s degree in information systems and my experience as a programmer/analyst to address business challenges in data processing. If you have been referred to a company by one of its employees, a career counselor, a professor, or someone else, mention that before stating your job objective.