The Keyboard Map
Learn the piano keyboard layout: half steps are the smallest move, two half steps make a whole step, and sharps and flats are two names for the same key.
The piano keyboard is a map of pitch: move right and notes get higher, move left and they get lower. Start by playing around — light up every key at least once.
Half steps: the smallest move
Any two keys that touch — black or white — are one "half step" (semitone) apart. That is the smallest move on the keyboard. Walk two half steps in a row and you have made a "whole step".
The black keys fill the gaps
Look closely: there is no black key between E and F, or between B and C. Those white-key pairs are already only a half step apart, so there is no gap to fill. Every other pair of neighboring white keys is a whole step apart, with a black key sitting right in the middle.
One key, two names
The black key between C and D can be called "C sharp" (C♯) or "D flat" (D♭). Different names, exactly the same key and the same pitch — which name you use depends on which side you are coming from.
Or use real keys
If you own a MIDI keyboard, plug it in and press CONNECT — from then on it plays every instrument on this site, with the weight of your touch and the sustain pedal coming through. Play a few keys and watch what it sends.
Plug in a MIDI keyboard, then press CONNECT. Your keys play everything on the site.
Challenge
Listen: are these two notes a half step or a whole step apart?