When using figures or captions, text should be left-aligned and at a slightly smaller font size. Text should be contextual, giving the picture in question meaning beyond what is clearly visible in the picture. Furthermore, captions should be fairly brief.
Anytime you need to display a piece of content—like an image with an optional caption, consider using the `figure` tag.
Use the included `.figure` , `.figure-img` and `.figure-caption` classes to provide some baseline styles for the HTML5 `figure` and `figcaption` elements. Images in figures have no explicit size, so be sure to add the `.img-fluid` class to your `img` to make it responsive.