Prameter in web service is not LOCAL

for functions if you keep the name as the same, all passed by value parameters should be like local variables. therefore you can change its name without affecting outside calls for this function. but it's not the case for web service, for example if you have an old web method
void ReturnContent(bool Secure)
and you changed it to void ReturnContent(bool IsSecure) , then it won't work as expected, and the web method will always default the value "IsSecure" to false since it failed to get the node from the soap message.