To ever have a chance of succeeding with your goal of landing that perfect job, you also need to dedicate some time and effort in crafting a good resume cover letter while ensuring that it maintains the structure of a proven and successful format. The cover letter essentially sums up your competencies and skills relevant to the role you are applying for. It is not generally considered as part of your resume, but you have to keep in mind that a cover letter becomes more effective if it complements your submitted resume.
Unlike a typical UK official letter format, the US has a couple of variations, the full block format and modified block format. The former simply means all elements of the letter, from the return address at the top down to the writer's name at the foot, are justified left. the latter, on the other hand, incorporates some elements to the right or centre, rather like the UK official letter format.