An axle is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearings or bushings are provided at the mounting points where the axle is supported.
A visual aid is something that supplements words with a picture, chart, or illustration. Looking at an image of the brain and the optic nerve as you read about it is a good example of a visual aid. It is a supplement to the words you're reading. Let's look at why you should use visual aids when you give a speech and the best ways to use them. Why Use Them. Imagine that you are going to present information to one of your classes.
Thus, visual aids should only be used when necessary. As per MLA style, visual aids are embedded directly into the document. Before anything, be sure to collect the appropriate sources and information required by MLA to properly document the visual aid (e.g. the source medium; print, Web, etc.). Be sure to think through which visual aid will best suit the intended purpose of the author. Consider how the use of a certain visual aid, such as a table or figure, will help aid in reader comprehension of the presented information. The visual aid that is used should be of absolute best quality.