I've found that optical media like CD-Rs and DVD-Rs corrode over time. Many of the CD-Rs I burned over the last 7 years are unreadable now. Different media seem

I've found that optical media like CD-Rs and DVD-Rs corrode over time. Many of the CD-Rs I burned over the last 7 years are unreadable now. Different media seems to degrade at different speeds. Beware of burning a DVD, storing it away for 10 years and trying to read it then.