Call me paranoid, but well. I fear system failure more than breaking an arm. Priorities. I've always been a Windows user, and I used to make a system image backup file that I'd write on a CD and store in case of disaster. Now with mac (running OSX 10.9.4 on late 2013 MBA), I'm not too sure if something like this is required. The only backups I have done and have been doing regularly are with Time Machine, and I thought Time Machine did the system image thing on the first backup too, but I learnt recently that this is not the case, that it only backs up my files, and that I cannot boot from a Time Machine backup. I know that I can do a system restore from startup, and I also know there are apps out there that can create a bootable backup for me on an external drive. Thing is, since these apps are not free and I also need to buy an extra hard drive for it, I'd like to know if this type of backup is necessary, convenient, and advisable because I'm broke (). Do you consider this is a must, or is it generally not an issue with macs? Thanks!