+.new
+.vitem &*${base64:*&<&'string'&>&*}*&
+.cindex "expansion" "base64 encoding"
+.cindex "base64 encoding" "in string expansion"
+.cindex "&%base64%& expansion item"
+This operator converts a string into one that is base64 encoded.
+
+.vitem &*${base64d:*&<&'string'&>&*}*&
+.cindex "expansion" "base64 decoding"
+.cindex "base64 decoding" "in string expansion"
+.cindex "&%base64d%& expansion item"
+This operator converts a base64-encoded string into the un-coded form.
+.wen
+