I am new to Node.js, but I wanted to start a new project and thought could be a good chance to learn the Node-Express framework and the MEAN stack.
What I'm confused about is why Express comes with the Jade template (*see EDIT) engine if the above mentioned stack uses, by definition, Angular. In fact, it is my understanding that although Jade could be used together with angular, this would be probably unnecessary and might just over-complicate things (see for example this question).
Of course I can see that Express could be used independently of such stack, so maybe let me put the question in a different way.
If it is true that it's not really necessary to combine Jade and Angular, what is the best way to go when building a web app in the MEAN stack framework?
Basically, what is the best way to go if one, after generating an express app using the Jade template, decides that he would like to use Angular (and Mongo)? So in case one started using the Jade template, would it be better to go back to plain HTML in order to use Angular?
It is probably just my ignorance in the field making me confused but some clarifications would be much appreciated.
EDIT: The original title was "Why does Express come with Jade if the MEAN stack uses Angular?" but thanks to the comments I realize that it's really not correct to say that Express "comes" with Jade so I changed the title as I was actually interested mostly in something else after all.