The crazy thing I did to fix Yosemite performance

[Ryan Schmidt]

On Nov 4, 2014, at 8:24 AM, Gustavo Seabra wrote:

>> Macs have always provided an incredibly easy way to create a bootable external harddisk (or thumb drive) and boot from it, everyone who is the least concerned about being able to repair or simply maintain the main boot disk should make use of that.
> 
> Can you tell me which tool is that?

There's no tool. You just use the normal OS X installer program to install onto an external disk instead of your internal disk.

But you might not even need that, because ever since OS X 10.7, you already have a recovery partition on your internal disk that you can boot to in case of trouble:

http://support.apple.com/en-us/HT4718