Js understanding that snippet

 

  const radgrad3 = ctx.createRadialGradient(95, 15, 15, 102, 20, 40);
  radgrad3.addColorStop(0, '#00C9FF');
  radgrad3.addColorStop(0.8, '#00B5E2');
  radgrad3.addColorStop(1, 'rgba(0, 201, 255, 0)');
  ctx.fillStyle = radgrad4;
  ctx.fillRect(0, 0, 150, 150);

And some are is (...) and other is = ...

And is because the first is a method or a function and the other is an assign a value, property or creating a variable and assigning for it a value. Rute Bezerra de Menezes Gondim