The cmap package is intended to make the PDF files generated by
pdflatex "searchable and copyable" in acrobat reader and other
compliant PDF viewers.

Just put the line \usepackage{cmap} at the beginning of your preamble,
and it will pre-load the needed CMap translations for the fonts used
in the document, provided that there exists the file <encoding>.cmap
for the font encoding.

Current version of the CMap package includes CMap files for the
following LaTeX font encodings: T1, T2A, T2B, T2C, T5.

Adding support for other font encoding does not require the change in
the cmap.sty package: just create the <encoding>.cmap file and make it
visible to TeX by putting it into the appropriate directory.

It works for Type 1 fonts, and also for Type 3 fonts (including the PK
fonts which are preloaded as Type 3 fonts into PDF) with recent
versions of pdftex.

The main limitation currently is inability to work with virtual fonts,
and this is because of limitation of pdftex, and may be resolved in a
future versions of pdftex.

It is possible to work around this limitation by creating a Type 3
font which implements instructions contained in the virtual font.
