r function calls available via the API
(Application Programming Interface), with the exception of the output text
formatting which is handled at the application level.</p>

<center><img src="overview.png" alt="ExifTool Overview" width="680" height="460"></center>

<p>The information flow is separated into two distinct modes: 1)
<span class=blu>Reading or extracting information</span>, and 2)
<span class=red>Writing or editing</span>.  The application runs in
<b class=blu>read</b> mode by default, but switch