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+# adobe-mappings-pdf
+
+Mapping resources for PDF have a variety of functions, such as mapping CIDs
+(Character IDs) to character codes, or mapping character codes to other
+character codes.
+
+These mapping resources for PDF should not be confused with CMap resources.
+While both types of resources share the same file structure and syntax, they
+have very different functions.
+
+These PDF mapping resources are useful for some applications (e.g. Ghostscript)
+to function properly.
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