fixed typo in readme

README.md

@@ -16,7 +16,7 @@ Manage your monthly budget easily with BudgetMaster
 - Password protected website - Your data can only be accessed by entering the correct password. (Note: The database is not encrypted)
 - Localization - English and German supported.
 - Search and Filter - Search for individual transactions or filter your view.
-- Visualize your data - Use on of the pre-defined charts or create your one by using the chart framework to visualize and analyze your data.
+- Visualize your data - Use one of the pre-defined charts or create your one by using the chart framework to visualize and analyze your data.
 - Auto Backup - Schedule an automatic export of your database content.
 
 ## Available Languages