I have arrived in Russia! Today is my first full day in St. Petersburg. I have walked around a bit and will be going to lunch soon. It is a very big city! After I am done here, I will travel to Moscow for a few days. Any suggestions on must see places here?

Formal/Informal/Swearing or Cursing When watching movies or shows or YouTube (in any language) it is such an informal place that it seems people are so open to use swear words. I know that here the the US, if you are among friends and family it can be used pretty freely depending on who is there. I am just wondering what it is like in the public areas of Russia, like Москва или Санкт П., and how the language is there? Is it ALWAYS formal if you don't know someone or are there exceptions? And is it looked badly upon if you swear?