Computer screens are often the recipient of mysterious smudges, spots and marks. Not only are they distracting, but these types of screen pollution can make it difficult to see what's on your screen. In some cases, computer screens — especially touchscreens — can even become fertile breeding grounds for bacteria.
If you're considering the best way to clean your computer screen, here's a great place to begin: use a clean, lint-free microfiber cloth. These fabric squares, like the ones used to clean eyeglasses, will remove dust that has built-up over time, and won't scratch the screen in the process. Simply turn off the computer (the dark, blank screen can help you see dust and other grime) and give the screen a series of horizontal swipes in one direction followed by vertical swipes — again, moving only in one direction. If you move the microfiber cloth in circles, it moves the dust around. By working in a grid, you'll not only remove maximum dust, but it will be easier to see what you may have missed.
What happens if you wipe the dust away, but still see spots or other indications of stubborn grime? Avoid using any type of household cleanser, like the kind you might spray on a window or counter because ammonia or alcohol-based cleaners can damage delicate screens — unless it is a glass screen like most Macs, and even then you'll want to be judicious with an alcohol-based cleaner and avoid using anything that will scratch the surface, such as a paper towel.
Your best bet is to make a homebrew of sorts, mixing a 1:1 ratio of distilled water (don't use tap water because it can leave mineral deposits) and white vinegar. This cleaning solution works well for screens without a glass coating, like LCD and touchscreens. Plus, if you're unsure about the type of screen you're cleaning, it's better to be safe than sorry. Spray the cleaning mixture directly onto the microfiber cloth, rather than the screen.
When in doubt, it's always a good idea to check with the screen's manufacturer — they may offer specific advice.