TweetMyMac is a software for Mac computers, these can be easily installed. Once you have installed the software you have the user specify one Twitter account, Twitter account for this it is to the beneficiary account, for example could the account “mactweet1 hot.  Best is to be a Twitter account and locks it for other people, it is not publicly twitters but in the “protected” mode, by none other than approved follower can see the tweets. If you have made these settings you can control his Mac computer via Twitter. There are various commands that perform various functions on the computer, these commands are sent via a direct message to the recipient account. About the shutdown command, the computer can be shut down and restart with the command lets you restart the Mac. All the commands with which you can control the Mac computer via Twitter you read on the manufacturers website, where there is a Detailed List the individual commands.