Trying to understand this t-sql if statement

I am working with someone else's code, and I just want to understand with this statement really means...

IF ((@TablesToCheck & 1) <> 0) {
   *Some bit of code*
}

@TablesToCheck is an int taken in via parameter. I get that this is checking if something is not 0, but I am not sure I understand what the (@TablesToCheck & 1) is. Is it just in-case @TablesToCheck is null?

Thank you.