How to insert another template into original templates?

[Alfa1]

Some simple questions, just to make sure that I understand this concept correctly:

- It is better to keep the original templates as clean as possible?
- So the best way to approach template modifications is to add new templates and to place a link to the new template in the original template?
- This is done as followed: if the name of the new template is mytemplate, then I will place the code $mytemplate in the original template?

What is the commonly used terms for such code? ($mytemplate)
Does this method add extra queries or server strain, when compared with just placing the added code in the original template?

[Opserty]

See this for the method: https://vborg.vbsupport.ru/showthread.php?t=166917#2

It may add an extra query but I think thats only if you don't pre-cache the template. There may be articles in the Article Section that shows you how to cache them.

[Alfa1]

That doesn't make any sense to me.