FocusWriter
FocusWriter is an open-source multi-platform application. It is simple and provides a free writing environment. This application helps students, it automatically saves progress and reloads the last files you had open to make it easy to jump back in during your next writing session, dismiss the siren songs of social media and YouTube videos so they can craft a perfect five-paragraph essay. It supports different OS like Linux, Windows, and Mac OS X. It has been translated into different languages.

Features

It provides the hide-away interface.
It provides a number of themes with different fonts, colors, and background images.
It shows live static of Word count, paragraph count, page count, and character count.
It supported Multi-document and session.
It can be translated into over 20 languages.
It supported TXT, basic RTF, and basic ODT files.

Brackets
Brackets is a lightweight and powerful open-source text editor. It is customizable and an easy entry point for students of all skill levels. It is supported by cross-platform like Mac, Windows, and Linux. It is written in HTML, CSS, and Javascript and released under the MIT License. It is available in 38 different languages. It provides a real-time connection to the browser. When we make changes to CSS and HTML and you can instantly see those changes on the screen.

Features

It provides a live preview of changes without a manual refresh file.
It provides the facility for a quick edit of your code.
It provides the support of JSLint that checks your Javascript code upon saving.
It provides the support of a number of extensions.
It provides an inline color picker for previewing and color adjustment functionality.

RedNotebook
RedNoteBook is a digital diary, it allows you to format, tag, and search your entries. It organized your work and provides the support to add pictures, links, and customizable templates, spell check your notes, and export to plain text, HTML, Latex, or PDF. For store data not required database, it stores data in the file. It is released under GPL License. It supported cross-platforms.

Features

It provides the support of export and allows you to export it as HTML, PDF, LaTeX, or plain text.
It provides support to browse notes by category or via a calendar.
It allows support to take backup your notes.
It provides a search function and integrated spellchecker facility.
Internet and e-mail addresses are recognized automatically as links.