imagine my delight when I started to notice every time I whistled a song, my cat would appear. And then I did it on purpose to test my theory, and indeed my cat who loves being alone & hiding, would come to me every time I whistled.
I have a cat that startles easily, so I started to click my tongue to warn her of my incoming pets if she's not looking. Now I can mace that noise and she perks up in excitement for the incoming love