-The first drives that came out used what called CD-Recordable disc's. These disc can only be written to one time and that's it. This is kind of a bummer but at least you can take 650 MB onto a disc. So that's not to bad. So how do these things work? How does the writer actually write?
-Well like on all CD's there are pits and places where there are no pits called (land). As discussed before this is what gives you the binary bits in 0's and 1's thus making data. Now we need a surface that the laser can carve the little pits in the CD. This is done by photosensitive dye's. There is what is called a polycarbonate substrate with prestamped grooves that is layered with photosensitive dye. The real action occurs in this layer. When exposed to a certain frequency of the lasers write head you have a pit. This is done by simply heating it up and changing the composition of the dye itself. Now we have pits with land in between making data.
-A real good side to CD-R disc's other than just recording is price. You can buy CD-R disc's for about a dollar. The Re-Write disc's are a little more expensive though.
