Update filenames to match short titles, add contentType frontmatter (#56836)

Co-authored-by: Sarita Iyer <66540150+saritai@users.noreply.github.com>

content/copilot/tutorials/copilot-chat-cookbook/document-code/explain-legacy-code.md

@@ -0,0 +1,121 @@
+---
+title: Explaining legacy code
+shortTitle: Explain legacy code
+intro: '{% data variables.copilot.copilot_chat_short %} can help with explaining unfamiliar code.'
+redirect_from:
+  - /copilot/example-prompts-for-github-copilot-chat/documenting-code/explaining-legacy-code
+  - /copilot/copilot-chat-cookbook/documenting-code/explaining-legacy-code
+  - /copilot/tutorials/copilot-chat-cookbook/documenting-code/explaining-legacy-code
+  - /copilot/tutorials/copilot-chat-cookbook/documenting-code/explain-legacy-code
+versions:
+  feature: copilot
+category:
+  - Documenting code
+complexity:
+  - Simple
+octicon: book
+topics:
+  - Copilot
+contentType: tutorials
+---
+
+One of the biggest challenges with legacy code is helping developers understand it who aren't familiar with the languages or frameworks. With {% data variables.copilot.copilot_chat_short %}, you can explain the background you have and ask for an explanation.
+
+## Example scenario
+
+Consider the following COBOL code. If you're a Python developer (as an example), you might not be familiar with COBOL, so you could ask {% data variables.copilot.copilot_chat_short %} to explain the code to you.
+
+```text
+IDENTIFICATION DIVISION.
+PROGRAM-ID. INSERT-RECORD.
+
+ENVIRONMENT DIVISION.
+
+DATA DIVISION.
+WORKING-STORAGE SECTION.
+01  WS-STATUS-FLAGS.
+    05 WS-DB-STATUS     PIC X(2).
+       88 WS-SUCCESS    VALUE "00".
+    05 WS-SQLCODE       PIC S9(9) COMP.
+    05 WS-ERROR-MSG     PIC X(50).
+
+LINKAGE SECTION.
+01  LS-PARAMETERS.
+    05 LS-PERSON-RECORD.
+       10 PERSON-ID     PIC 9(6).
+       10 PERSON-NAME   PIC X(50).
+       10 PERSON-AGE    PIC 9(3).
+    05 LS-RESULT        PIC X.
+       88 SUCCESS       VALUE 'T'.
+       88 FAILED        VALUE 'F'.
+
+PROCEDURE DIVISION USING LS-PARAMETERS.
+    PERFORM INSERT-AND-VALIDATE
+    GOBACK
+    .
+
+INSERT-AND-VALIDATE.
+    EXEC SQL
+        INSERT INTO persons (id, name, age)
+        VALUES (:PERSON-ID, :PERSON-NAME, :PERSON-AGE)
+    END-EXEC
+
+    IF SQLCODE = 0
+        EXEC SQL COMMIT END-EXEC
+        SET SUCCESS TO TRUE
+    ELSE
+        EXEC SQL ROLLBACK END-EXEC
+        SET FAILED TO TRUE
+        STRING "DB Error: " SQLCODE
+            DELIMITED BY SIZE
+            INTO WS-ERROR-MSG
+        DISPLAY WS-ERROR-MSG
+    END-IF
+    .
+```
+
+## Example prompt
+
+You can ask for an explanation of the COBOL code from the point of view of a Python developer.
+
+`I'm a Python developer. Help me better understand this code. Please provide analogies.`
+
+## Example response
+
+{% data reusables.copilot.example-prompts.response-is-an-example %}
+
+{% data variables.product.prodname_copilot_short %} provides a high-level overview of the code, before walking through the various operations and explaining them in a way that Python developers can understand. It uses analogies to make the explanation more accessible. The response might start with the following:
+
+```text
+Let me explain this COBOL code using Python analogies:
+
+High-Level Overview
+This is similar to a Python function that inserts a person's record into a database with error handling.
+```
+
+```python
+# In Python, the COBOL divisions would be like:
+
+# IDENTIFICATION DIVISION = module/file name
+# PROGRAM-ID = function name
+def insert_record():
+    pass
+
+# DATA DIVISION would be like declaring these variables:
+class WorkingStorage:
+    db_status = ""  # WS-DB-STATUS
+    sqlcode = 0     # WS-SQLCODE
+    error_msg = ""  # WS-ERROR-MSG
+
+# LINKAGE SECTION is like function parameters
+class PersonRecord:
+    def __init__(self, person_id: int, person_name: str, person_age: int):
+        self.person_id = person_id    # PERSON-ID
+        self.person_name = person_name # PERSON-NAME
+        self.person_age = person_age   # PERSON-AGE
+        self.success = False          # LS-RESULT
+```
+
+## Further reading
+
+{% data reusables.copilot.example-prompts.further-reading-items %}