Half step and whole step

Half step
is the distance on the piano from the one note to the very next note wether it is white or black
example :
B - C = half step
C# - D = half step
D - D# = half step
D# - E = half step

Whole step

is two half step
example :
B - C# = whole step
C# - D# = whole step
D - E = whole step
D# - F = whole step