When a user visits a site they are presented with some sort of Navigation Structure. Typically the arrow is a standard convention that alerts a user that when this item is clicked an action will occur. It can be presented from expandable side navigation, returning to a previous page to other multiple actions.
Throughout navigating various websites on personal computers to mobile devices I have noticed that arrows can be a bit misleading. Some sites give the impression their side-navigation expands but once you click the item the user is directed to another page or vice-versa.
Through research I have noticed sites like Think Geek using arrows to direct users to new pages while plus signs are used to display expandable content.
CSS-Tricks uses a longer version of the arrow that directs users to a new page with more information.
You-Tube has used arrows on multiple items that almost seem to be over-abundant, unneeded, and a little confusing.
Can Arrows have multiple uses from expanding content to directing users to a new page? Are there any best practices regarding the usage of arrows on websites?