command1 & command2
Use to separate multiple commands on one command line. Cmd.exe runs the first command, and then the second command.
command1 && command2
Use to run the command following && only if the command preceding the symbol is successful. Cmd.exe runs the first command, and then runs the second command only if the first command completed successfully.
command1 || command2
Use to run the command following || only if the command preceding || fails. Cmd.exe runs the first command, and then runs the second command only if the first command did not complete successfully (receives an error code greater than zero).
(command1 & command2)
Use to group or nest multiple commands.
; or ,
command1 parameter1;parameter2
Use to separate command parameters.