How many country in the world?

There are around 195 countries. Although it depends whether you consider some independent states or not to be countries.

It depends. Some countries don't recognize other countries as real countries.

Generally, there are about 194-196 countries recognized. But to be more exact, It is considered to be about 196 countries in the world although some countries, including the U. S, don't recognize Taiwan as a country although it "acts" like a country so that will bring it down to 195.