Images help tell a story where describing with words is either too lengthy, or practically impossible. For instance, you could have a map of a location and various arrows and other markings to describe movements of troops during a battle of the civil war. This is one example of many that you could have as an image on a website. Describing the troop movements with words only may be really difficult to do. Plus many people are visually oriented learners, so they benefit with images every now and then. Of course, it's best not to overdo things and overload the site with too many images. A nice balance is needed.
Answer:
Simple Mail Transfer Protocol (SMTP) is the standard protocol for sending emails across the Internet.
Opacity is the extent to which something blocks light. You can change the opacity of layers, filters, and effects so that more (or less) of the underlying image shows through.
The answer is pavement markings. Hope I helped! :)
