update README

README.md

@@ -7,6 +7,8 @@ _Access Aide_ is a Calibre (book editor) plugin to enhance epubs with accessibil
  -  Add accessibility declarations to book metadata.
 
 # Usage
+This plugin can be used as part of an InDesign-based workflow to produce accessible epubs. InDesign is capable of adding language information to OPF files and appropriate epub:type to html tags. Access Aide reads this information and add language declarations, aria roles and metadata statements to comply with the WCAG 2.0 – AA guidelines for accessible publications.
+
 ## Config
 Plugin behaviour can be fine tuned via plugin config dialogue.
 
@@ -20,6 +22,6 @@ Open the book to enhance in the Calibre ebook editor and start Access Aide. This
 # License
 Source code by Luca Baffa, released under the GPL 3 licence.
 
-This project is _heavily influenced_ and inherits part of the code from the [Access-Aide](https://github.com/kevinhendricks/Access-Aide) LGPL v2.1 plugin developed for Sigil.
+This project aims to port the functionalities of the excellent [Access-Aide](https://github.com/kevinhendricks/Access-Aide) LGPL v2.1 Sigil plugin to Calibre.
 
 The plugin icon (`./icon/icon.png`) comes from the `adwaita-icon-theme` pack ([gitlab page](https://gitlab.gnome.org/GNOME/adwaita-icon-theme) of the project), released as LGPL v3 by the GNOME Project.