What does "~/" mean in directory path?

 Can anyone tell me what does it mean "~/" in following example?
private String filePath =
            HttpContext.Current.Server.MapPath
                ("~/App_Data/Authors.xml");
Is it same as private String filePath =
            HttpContext.Current.Server.MapPath
                ("./App_Data/Authors.xml");
 
Thank you!
Best Regards
Lynda

 
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