In this chapter, we've reached the limit of complexity we need to create themes. Customizing block templates isn't always necessary, but it's sometimes the icing on the cake. If you look around the concrete5 marketplace, you'll find a bunch of themes that don't contain any block templates; but those that are popular usually ship with a few block templates.
Even if you don't intend to distribute your themes in the marketplace, block templates might still be required to suit the needs of either you or your customer. If you don't have a lot of PHP experience, this part can be a bit tricky; but keep in mind that block templates can often be reused in different projects. Spending some time to build a set of block templates you know how to work with can give you a lot of benefits, especially if you intend to develop your business.
There's one more chapter in which we'll make sure that all of these things work on a device with a smaller screen as well, adding the final piece to make a quality...