> And that's important how?
The technique helps the readability of long data tables for everyone. In print, we have ledgers and lined computer paper. Alternating the very high contrast is just a variation on a theme.
> JavaScript and/or CSS can do that.
Can you suggest the selector? I have used <tr class="odd"> and <tr class="even"> but this seemed like too much work to get the effect. Should there not be a way for an element to figure this out for itself? (I have added the class to every row when generating the data table programatically, but still this seems very inelegant, although I was pleased with the end results.) Maybe CSS needs a pseudo-element like first letter and line for this? How would an end-user achieve this with a custom override style sheet?
> If you just want to highlight a row,
> tr:hover will do it in non-braindead browsers.
I like that!