Backup Advice
People often come to me asking how to backup. Or worse, they come to me not having backed up their files, and want to know if I can recover their data. While I can often help people recover their lost data, it is far better to be prepared with a backup plan. It's also much less of a mess once the data is recovered.
My advice: Be Prepared! Get yourself a backup drive NOW!
Remember, if you're a Mac user, you may want to re-format the drive for better performance (these drives are by default formatted for Windows). You can do this with Apple's Disk Utility, in the Utilities folder - look at the "Go" menu from Finder.
macOS comes with "Time Machine" which can help you back up your files automatically.
Another backup application I like is Carbon Copy Cloner.
I suggest programming your backup application to do a daily backup at a time when the computer is usually on. The nice thing about daily backups is that, if you miss one, it's not a big deal. Also be sure to have your software do incremental backups, so that your entire disk isn't re-copied every time.
If you're a business you may want a more comprehensive backup plan which includes a clone of your most critical data, archives of deleted and changed data, as well as swappable drives for keeping a copy of your data safe offsite in case of fire or theft.
For a more detailed walkthrough of backup strategies, including the 3-2-1 rule and cloud backup options, see my Complete Mac Backup Guide.
Already Lost Data?
If it's too late for backups and you've already lost data, visit the homepage for data recovery resources including a discount link to DriveSavers.