Loading at a switch

Hi guys,

Sorry for the simplicity of this question, guess it’s a reflection of my own limited network traffic knowledge! But I have been studying Network Traffic, Simulation, Erlang etc. and two terms that have come up are ‘load at a switch’, which I understand but what is ‘loading at a switch’? I have looked over old exam questions and in one year these two things were asked side by side so I know it’s not a miss type or whatever. ANY help would be really appreciated. Thanks guys.