Significance of line vty 0 4

VTY is remote landing router virtual port, 04 represents the five sessions can be opened at the same time, line vty 0 4 entering VTY port for VTY port configuration, for example configuration code, or ACL. 
Enter 00 if no practical significance VTY, this is the first open remote login, even if doing this restriction, also landed from 1. 
line vty 0 1180 is also available in 1181 to allow remote access terminal. 
General equipment is a console port, which is the console 0