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@@ -3,14 +3,27 @@
 
 ## Introduction
 
+ResInsight is a tool for visualizing Eclipse Reservoir simulation related data, and aims to be 
+fast, accessible and flexible and to contain tools and visualization modes requested and designed by 
+Reservoir engineers.
+
+The main input data is
+`*.GRID` and `*.EGRID` files along with their `*.INIT` and restart files `*.XNNN` and `*.UNRST`. 
+ResInsight have some support for Eclipse input files, often called `.grdecl`, and can read grid 
+information and the corresponding cell property data sets.
+
+ResInsight also have support for extensive processing of the data sets through an interface to octave, and 
+can also export modified cell property data sets to single Eclipse input files.
 
 
 ## Getting Started
-
 ### Installation
-
 ### User Interface Overview
-
-### Navigation
+#### Navigation
+#### Toolbars
+### Project files `*.rsp`
+
+
+