Wikipedia:Tip of the day/January 11
A caption to an image is a title, a label with several essential purposes. If all are fulfilled, specific formats are a matter of taste, but they should be fairly consistent within an article, for the reader's sake. Not every Wikipedia image needs a caption: some are simply decorative. A very few may genuinely be self-explanatory. If you decide that an image does not need a caption, then please follow the advice at Wikipedia:Alternative text for images to specify appropriate "alt" text. Captions can be added by using the frame or thumb paramater as part of an image tag. For example: [[Imagename.jpg|frame|Write the caption here.]]. Remember that some images, such as logos or element symbols, should not have captions.
Read more: Wikipedia:Captions