If you store ANY information that’s important to you on your computer – documents, pictures, music, etc. – back it up. Do it. Back it up right now. Go ahead.
Make sure your backup is stored offsite. Back it up to a “cloud” service, a flash drive, an external hard drive, DVDs, or ??? But get it out of the house.
Don’t worry about backing up “programs.” Just get the data, as mentioned above. Programs need to be reinstalled anyway. Update your backups often. Once a week, once a month, whatever you’re comfortable with. Because once it’s wiped out, it’s gone.