Sending personal letters was replaced by emails years ago, at least for the most part. . Addressing an envelope properly helps get your letter to the correct destination on time. In addition to this, it is good to put the your persoanl adress at the right position more so when writing a formal letter. An individual's personal address should be on the Top right hand corner of the writing pad and the receivers address should be on the left hand corner, left justified just a line below one's personal address.