I got stuck on tutorial

[vitamin]

I think i've already found the answer!

Face|Mirror command just mirror the object around the selected faces.
(ever keep your attention in Info Line when your cursor are over a command: in this case, there is a difference between click with left or right mouse buttons - you can read the instructions there).

Tools|Virtual Mirror|Create command creates a virtual mirror "condition", ie, everything you do is duplicated at both sides of objects, better saying, at both sides of virtual mirror plane (until you call Tools|Virtual Mirror|Freeze, when you finished that "virtual mirror session").

Thank you for this straightforward explanation. Today, at last I finished my first 3D model ever



But I'd like to ask about that smoothing tool. What is it for actually? A smoothed preview gives me a roughly estimated view of my model in a game maybe? Or let's say that I would like to model a real car from a reference image - does it mean I need to model while having that smoothing turned on?