CD-RW
A Compact Disc ReWritable.
That is you can burn (write) onto the compact disc then erase the contents of the disc and write to it again.
The downside is the number of times you can rewrite to the disc is limited and there are extra steps to ensure others can read what was written on their systems. Which includes "closing" the disc as written too.
With the cheap cost of CD-R (write once) the CD-RW never caught on in popularity.
