Having one or more backups is essential.
Sooner or later, you most likely will have something go
wrong and lose your personal files, documents or photos.
Examples include accidentally deleting the wrong files,
hardware failure, losing your laptop or infecting your
computer. At times like these, backups are often the only
way you can rebuild your digital life.
OUCH! -- Backup & Recovery
Use Time Machine to back up or restore your Mac
OS X El Capitan: Time Machine options preferences
OS X El Capitan: Connect a new backup disk to your Mac
Backup to external Hard Drive or Flash via command line
rsync -av -e ssh /Users/swormley /Volumes/My\ Passport
rsync --delete -av -e ssh /Users/swormley /Volumes/My\ Passport
Backup to another computer on LAN via command line
rsync -av -e ssh `pwd`/ mm3.local:`pwd`
Recall Dropbox (Free service for all platforms)
Dropbox is a file hosting service operated by Dropbox, Inc.,
headquartered in San Francisco, California, that offers
cloud storage, file synchronization, and client software.
Dropbox allows users to create a special folder on each of
their computers, which Dropbox then synchronizes so that it
appears to be the same folder (with the same contents)
regardless of which computer is used to view it. Files
placed in this folder also are accessible through a website
and mobile phone applications.
One can backup specified files and folders to Dropbox using
symbolic links via the command line. For example:
ln -is ~/Documents ~/Dropbox/Documents
Anything added, deleted or changed on the Mac is replicated
in Dropbox and vice versa. Deleting File/Folder in Dropbox
also deletes it immediately from the Mac! Just so you know.
Using The Cloud Securely
iCloud Backup & Storage
Carbonite (backup in the cloud)
Crashplan (backup in the cloud)