--- a/doc/User-oriented-commands	Sun Feb 14 19:01:04 2021 +0000
+++ b/doc/User-oriented-commands	Sun Feb 14 23:03:00 2021 +0000
@@ -101,3 +101,81 @@
 unblock-pin2 PUK2-secret-code new-PIN2
 
 Unlike PIN1, PIN2 cannot be disabled per traditional SIM card standards.
+
+Getting basic info from the SIM
+===============================
+
+The following commands are available for retrieving basic info from the SIM:
+
+iccid
+
+This command retrieves the ICCID (Integrated Circuit Card ID) record from the
+SIM - it is a number of up to 20 digits (although 19-digit ICCIDs are most
+common) that identifies the SIM card as a physical artifact.  If your SIM is of
+the traditional operator-issued kind, as opposed to a developer-oriented
+programmable SIM from vendors like Sysmocom who have different ideas, this ICCID
+will usually be the SIM card ID number printed on the physical plastic, along
+with a barcode representation of the same number.
+
+imsi
+
+This command retrieves the IMSI (International Mobile Subscriber Identity) from
+the SIM - it is the most fundamental ID token by which GSM phones present
+themselves to networks, and they even use the first 5 or 6 digits of the IMSI
+to decide which network they should try connecting to first.
+
+sst
+
+Every SIM card is required to have an essential data record (an EF in technical
+terms) called the SIM Service Table, or SST.  This SST indicates which services
+are allocated and activated on the given SIM.  Our sst command lists all
+allocated service numbers, listing just a plain number if the service is both
+allocated and activated (the usual case), or a number with a '^' suffix if the
+service is allocated but not activated.  You will need to look in the 3GPP TS
+51.011 spec to make sense of these service numbers.
+
+user-sum
+
+This command displays a user-friendly summary of user-oriented services present
+on the SIM.  It reads SST to get the list of available and activated services,
+but it considers only user-oriented ones (as opposed to SIM services dealing
+with GSM network functions or serving operators' interests rather than users'),
+and it displays them in a user-friendly manner.  For each present SIM phonebook
+(ADN, FDN, SDN) and for the SMS store, user-sum displays the storage capacity
+provided by the SIM (number of phonebook entries or messages), and for each of
+the various phonebooks, the allocated number of alpha tag bytes is also
+displayed.
+
+The number of bytes allocated for the alpha tag in SIM phonebooks determines
+the maximum length of the name field in each phonebook entry.  These name fields
+can be written either in GSM7 encoding (GSM 03.38 aka 3GPP 23.038) or in UCS-2;
+when GSM7 encoding is used, no SMS-style septet packing is applied - instead the
+high bit of each byte is simply cleared.  Therefore, the maximum number of
+characters in a phonebook entry name field usually equals the number of bytes
+allocated for the alpha tag on the SIM, except for names containing ASCII
+characters [\]^ and {|}~ which get expanded to 2-character escape sequences in
+GSM7 encoding.
+
+uicc-dir
+
+If your SIM card functions not only as a classic GSM 11.11 SIM, but also as a
+UICC with USIM/ISIM or other UICC-based applications, it will have a file named
+EF_DIR in its file system, listing those applications.  fc-simtool uicc-dir
+command dumps the content of this file in a human-readable form - but please
+note that fc-simtool only speaks the classic GSM 11.11 protocol to the SIM, and
+not the UICC protocol.  EF_DIR does not officially exist in the classic GSM SIM
+spec, hence the dir command in fc-uicc-tool (speaking the UICC protocol) is the
+official way to read and dump the content of EF_DIR.
+
+Manipulating SIM phonebooks
+===========================
+
+Manipulating stored SMS
+=======================
+
+Manipulating SMS profiles
+=========================
+
+Identifying MVNO SIMs
+=====================
+