The piano keyboard is constructed with black and white keys. The black keys alternate: two black keys then three black keys. These two groupings of black keys are separated by a space where there is no black note. The scale of C is the scale which is formed by playing all the white notes between a low C and the C an octave above. If you look at the keyboard below, from C to D (there’s a black note in between) the distance is a whole step. From D to E the distance is again a whole step; from E to F (since there is no note in between) the distance is a half step; from F to G, the distance is a whole step; from G to A, another whole step; from A to B, another whole step; but from B to C the distance is a half step. So the major scale formula is: two whole steps plus a half step plus three whole steps plus another half step.
Or you could write it like this: 1, 1, 1/2, 1, 1, 1, 1/2. As long as you keep these same musical relationships, a major scale can be made on any note. Another name for a whole step is a “Major second” and another name for a half step is a “minor second”.