The Wake-on-LAN (WOL) tool allows you to send a target host a Wake-On-LAN magic packet which directs a sleeping system to wake up (if the network interface is enabled to do this usually through the BIOS). IP and MAC address of target system are required.
There are two modes, single and batch. Single sends a UDP packet containing the 'magic packet' information to the port of your choice on a single machine or all machines on a LAN. The batch mode allows you to create a list of IP and MAC addresses. All will be sent the magic packet at the same time in batch mode.