Mellel is a word processor for Mac OS X, developed since 2002 and marketed as especially suited for technical and academic writers, and for writers with long, complex documents. It is made by Mellel AAR, a small software company. New features are added to the program every few months, many of which come from user suggestions. Its closest competitor is Nisus Writer Pro. One remarkable feature present in Mellel is its multilanguage support. Languages with non-Latin alphabets, including Arabic, Syriac, Hebrew, Greek, Korean or Persian, for example, are handled well due to the fact that Mellel sports its own text engine, that is not reliant on macOS text support, and in addition support for Unicode and OpenType fonts. Mellel also presents a feature set suitable for working with long and complex documents, in order to match the needs of scholars and technical writers. Mellel has a distinctive way of handling footnotes and endnotes, allowing creation of numerous "streams" of notes in a single document. This feature allows including, three or more types of footnotes at the same time. Cross-references are also dealt with in a singular way by Mellel. The software offers support for Outline, based on headings in the document text. With Mellel 4.0 the software added an Index tool which according to the company website "rivals dedicated Index applications". Mellel has a unique way of handling styles, which are also organised as part of a style set, that can be utilised by multiple documents. Its Replace Styles feature is able to reformat a large amount of text scattered throughout a document. Due to its unique approach to implementing many of its features, Mellel originally lacked full compatibility with standard word processors, but--as of July 2020--Mellel exports accurately to.docx and to ePub according to the developer's website. From the outset, Mellel has exported accurately to.pdf. Mellel provides tight integration with Bookends and Sente, bibliographical tools for managing citations, including Live Bibliography. A version of Mellel is available for the iPad. Owners of Mellel announced in January 2011 that they will give free updatesfor life for anyone who will purchase the application outside the Mac App Store. As per the company, this policy was dropped in February 2014. With the release of Mellel 4.0 Mellel AAR, the developer, announced that a for fee upgrade policy was re-instated. This policy does not apply to users who've purchased Mellel during the "lifetime" period. The current version of Mellel, 5.0, reportedly supports MacOS 10.7X or later. Although Mellel is compatible with OS 10.15 Catalina, users may not want to upgrade to Catalina if, e.g., they use MathMagic or MathType to insert equations. These are not 64 bit compatible as of July 2020.