I have this in some React documentation, as well as screencasts. People will write
{ " " }
This is used to put an explicit space in a text block, since leading and trailing spaces are ignored at compile/transformation time when there is another tag.
Example:
<div>
Text
<a>some Text</a>
</div>
Will result with Textsome Text
on the screen. (see the missing space)
<div>
Text{' '}
<a>some Text</a>
</div>
Will result as wanted with Text some Text
on the screen.