As mentioned, the most important thing to gain from this chapter is not just the use of these three new features (although, they are very useful in themselves), but rather the process behind adding them. To summarize, you should:
Think about what you want to add to the site and ensure it relates well with the business goals of the site.
Perform a fairly in-depth requirements analysis so that you know what type of functionality you are working towards implementing.
Back up your site before beginning any work on the additional material.
If you are writing your own code, then you need to plan how everything will fit together before embarking on the coding process.
Create, write, and/or install the feature.
Thoroughly test everything about the new feature and confirm that all the wrinkles have been ironed out.
Analyze any possible security holes and spend some time thinking about how you might try to break this new code. (If you don't, others certainly will.)
Back up...