This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
nobr tag prevents a text from breaking into a new line automagically, so it is displayed on one long line and scrolling might be necessary. This tag is not standard HTML and should not be used. Instead use the CSS property
white-space like this:
<span style="white-space: nowrap">Long line with no breaks</span>