assembly - Push/Pop vs Mov in MASM -

is a simple question but I do not know the answer.

The reason for this is:

  push wParam pop char   
 Where  wParam  is the type of WPARAM type Is defined in form and  char  is defined as the type WPARAM.  
 Why can not I just do it  
  mov char, wParam   
 I think what to do with this address, but I can not justify it. When I try to use the  mov  statement, MASM excludes a non-discript error.  
  
 
 
 Because both are memory addresses and in x86 assembly  mov mem, mem  ( There is no such instruction as  mov char, wParam  in this case).  
 So, to do this, you should press  push  & amp; Move the value into some register with  pop , or before  mov reg, mem  and from that register to  mov mem, reg .