Nested templates are similar in nature to linked templates. Just as linked templates allow the execution of a separate template from the master template, nested templates help to execute others. However, there are notable differences between the two types.
While linked templates are separate templates and thus stored separately, nested templates are instead defined within the same master template file. While linked templates should be available at a well-defined URI accessible to the master template, there is no such requirement for a nested template. In addition, linked templates should be protected from unauthorized access, while nested templates need not.
However, there are certain constraints to consider before working with nested templates. For example, nested templates do not have the ability to define their own parameters; nor do they return any values...