how nopcommerce multi language works?

I want to create multi language mvc site with database and saw nocommerce multi language implementation but i did not understand so mush. can anybody guide me how this implementation work?or is there any references to implement mvc site multi language with database?

It may helpful for you===>http://docs.nopcommerce.com/display/en/Localization

And also ==>https://www.codeproject.com/Articles/1160340/Get-insight-to-build-your-first-Multi-Language-ASP

sohel wrote:

thanks for your replying but in this tutorial use resource.resx.
i want to create this key and values in database and read from that like nop.
i understood what nop do but i did not understand how key get value after changing language or in start.