LaTeX users sometimes need to ensure that two or more blocks of
text occupy the same amount of horizontal space on the page. To
that end, the eqparbox package defines a new command,
\eqparbox, which works just like \parbox, except that instead
of specifying a width, one specifies a tag. All eqparboxes with
the same tag--regardless of where they are in the document--
will stretch to fit the widest eqparbox with that tag. This
simple, equal-width mechanism can be used for a variety of
alignment purposes, as is evidenced by the examples in
eqparbox's documentation. Various derivatives of \eqparbox are
also provided.
