{{{1}}}
This template takes some text as its first argument and simply re-emits it, but prevents line wrapping by surrounding it in a span with white-space: nowrap. Compare:
| Heading 1 | Heading 2 |
|---|---|
| Long cell content | More long cell content |
with
| Heading 1 | Heading 2 |
|---|---|
| Long cell content | More long cell content |
(You will probably have to reduce the horizontal size of your browser window to see the difference.)