Biber is a bibliography information processing program that works in conjunction with the LaTeX package BibLaTeX and offers full Unicode support.

Both generate a bibliography in LaTeX, but Biber offers a large superset of BibTeX functionality.

It also offers full Unicode support, which is hard to achieve with BibTeX.

The most important example is natbib, which provides style options for citation references.

[5] However, natbib functionality can largely be recovered by using the natbib option to BibLaTeX, which is the LaTeX package for processing citation references that is commonly used in conjunction with biber.