Can you just remind me where that code comes from? Which Course and Module/Unit? (Or post the link to my Github code)
Thanks!

it’s in Ethernet Web Server (Relay + Temperature) project inside Arduino Step-by-step Projects Course

Got it, thanks! Basically this is how you declare a function:

void dashboardPage(EthernetClient &client) {
  // your function
}

• void – means that your function doesn’t return any value (it only performs a certain action)
• dashboardPage() – it’s the function name that you use too call it
• EthernetClient &client – you pass the client connection as a parameter
• // your function – where you place your code to run when you call that function (in this case it send the HTML page/dashboard to the connected client)

I hope that helps!

thanks a lot i only didnt get why you use & in this code what is the advantage of that operator &

That “&” returns the address (in physical memory) of the client variable.