The more recent emergence of remote laboratories caused some discussions about their real educational value, when compared to traditional hands-on and virtual laboratories. This discussion is relevant because remote labs rely on computer-mediated access to real instruments and apparatus, being sometimes difficult to explain the difference between values obtained from real (remote) measurements and values obtained from computer simulations. This paper aims to evidence aspects that differentiate remote and virtual laboratories, by presenting two very simple experiments dealing with the characteristics of real instruments (limited bandwidth) and real circuits (electromagnetic interference). © 2017 Association for Computing Machinery.