Input cheatsheet

Keyboard

if (Input.GetKeyDown(KeyCode.Space)) { 
    // Space key was Pressed
}
if (Input.GetKeyUp(KeyCode.W)) { 
    //W key was Released
}
if (Input.GetKey(KeyCode.UpArrow)) { 
    // Up Arrow key is being held down 
}
if (Input.GetButtonDown("ButtonName")) { 
    // Button was pressed
}
if (Input.GetButtonUp("ButtonName")) { 
    // Button was released
}
if (Input.GetButton("ButtonName")) { 
    // Button is being held down
}

Button, Mouse & Touch Input located under Edit » Project Settings » Input

Mouse

if (Input.GetAxis("Mouse X") < 0) {
    // Mouse moved left
}

if (Input.GetAxis("Mouse Y") > 0) {
    // Mouse moved up
}

if (Input.GetMouseButtonDown(0)) {
    // Pressed primary button.
}

if (Input.GetMouseButtonDown(1)) {
    // Pressed secondary button.
}

if (Input.GetMouseButtonDown(2)) {
    // Pressed middle click.
}

Touch

if (Input.touchCount > 0) {
    touch = Input.GetTouch(0);

    if (touch.phase == TouchPhase.Began) {
        // Touch began
    }

    if (touch.phase == TouchPhase.Moved) {
        // Touch moves
    }

    if (touch.phase == TouchPhase.Ended) {
        // Touch ended
    }
}