Directives and plugins are ways to package functionality in a reusable way and also make it easily shareable across apps and teams; you will build a few of them in this chapter. Render functions are how Vue really works under the hood to turn templates into the Vue language and then into HTML and JavaScript again; they become useful if you need to optimize the performance of your apps and work in some corner cases.
In general, you should avoid using these advanced functions when possible as they have been a little overused in the past. Usually, many problems can be solved by simply writing a good component and distributing the component itself; you should look at advanced features only when this is not true.
This chapter is for the slightly more experienced, and you probably won't find the level of step-by-step detail found in other recipes, but I have strived to make them complete nonetheless...
