Smoke Testing=Sanity Testing

Despite of hundreds of web articles on smoke and sanity Testing, The people have confusion on it
I think there is no any difference between these two, both are used for verification purpose some people will say sanity can used when the new build is ready to test, here the job is to test whether the requirements are build for the project and smoke is used at the middle, end stage to check whether the Requirements are build for the project or not

I found only the spelling mistake between these Two

It depends upon the work place the people will show the difference, in my place there is no any difference