Learn Hardcore Russian: Скажите, пожалуйста, какое сегодня число? — Сегодня вторник, пятое марта. - Please tell me, what is today’s date?

In Russian, сказать basically means to say / to tell, depending on context. In questions like Скажите, пожалуйста..., it functions very naturally as a polite way to say Tell me, please... or Excuse me, could you tell me...

So Скажите, пожалуйста, какое сегодня число? is a standard polite way to ask for information.

Also, скажите is the formal/plural imperative form, so it is used:

when speaking politely to one person
when speaking to more than one person

That is why it sounds respectful.

What exactly does пожалуйста do in this sentence?

Пожалуйста means please here.

So:

Скажите = tell me / say
пожалуйста = please

Together, Скажите, пожалуйста... is a very common polite opener, similar to:

Please tell me...
Could you tell me, please...
Excuse me, could you tell me...

It softens the question and makes it more polite.

Why is the question какое сегодня число? and not something like какой сегодня день?