Writing business letters (and memos) are extremely important in the professional world where people are busy and professional. It is important to learn how to write proper business letters to quickly get your point across and not ramble. You need to inform quickly, and concise. Personal conversations can be done elsewhere, right?
Properly writing/filling out job applications (and resumes) is also important to us because they are used for every job nowadays. When writing job applications you can't ramble about your experiences or this and that. It is important to learn this so you can "GET A JOB"!
No one enjoys a dull website. If you are going to create a website that isn't specifically for entertainment or the like, you have to spice it up a bit in forms of text font, size, and color, including backgrounds and pictures/animations.
