Kate
Kate is a professional programming text editor that no coder should be without. Syntax highlighting extends to over two hundred types of code file, and file encoding is automatically detected. The powerful search and replace feature can also perform actions across multiple files, including those accessed over web protocols.
Kate also includes an emulation mode that mimics the modal behaviour of the command-line vi editor and its key shortcuts. It is also possible to expand Kate's functionality with additional plugins that include the likes of file browsers and spell checking.
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Libre Office
Libre Office is the established standard for office productivity in the open source world. With it you get just about everything you could ask for in terms of word processing, spreadsheets and presentations, without all the unnecessary bloat of Microsoft Office.
For those who can't escape the world of Microsoft entirely, Libre Office has a high level of compatibility with all Word/Excel/Powerpoint formats that you'll be expected to work with to get your job done. Chances are, if you installed a standardised Linux distribution in the past few years, Libre Office was already included.
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