I am working on a project in which there is a lot of HTML code repeated, for which I have decided to use templates, I was researching and discovered that files with extension tag and jspf files can be used, the problem is that I am not very clear on what time to use each type of file and if it represents any type of inconvenience in the performance of the application. I would also like to know if I can insert in some way scriplets in the content of the templates that you have created.