doc updated

Author: sujancse

README.md

@@ -3,7 +3,7 @@
 ![GitHub](https://img.shields.io/github/license/sujancse/php-csv-exporter?color=yellow)
 
 ## Overview
-A fast and tiny PHP library to export data to CSV, Excel, etc. The library is based on a PHP generator. It used only 20MB memory to download 5 Million data, whereas without generator it will take up to 500MB of memory. Tested on Laravel 6.
+A fast and tiny PHP library to export data to CSV and ExcelSheet. The library is based on a PHP generator.
 
 ### Installation
 ```$xslt