diff --git a/06-join.md b/06-join.md
index b8e3cb60..0524ba1d 100644
--- a/06-join.md
+++ b/06-join.md
@@ -1070,6 +1070,10 @@ read_back_csv.head(3)
 ```
 
 The CSV file contains the names of the columns, but not the data types.
+A keen observer may note that the `dataframe` that we wrote to the CSV file did not contain data types, so it is unsurprising that 
+the CSV file also does not. 
+However, even if we had written a CSV file from an astropy `Table`, which does contain data type, 
+data type would not appear in the CSV file, highlighting a limitation of this format.
 Additionally, notice that the index in `candidate_df` has become an unnamed column
 in `read_back_csv` and a new index has been created.  The Pandas functions for writing and reading CSV
 files provide options to avoid that problem, but this is an example of
diff --git a/md5sum.txt b/md5sum.txt
index 3fa46337..4ebcf1ea 100644
--- a/md5sum.txt
+++ b/md5sum.txt
@@ -8,7 +8,7 @@
 "episodes/03-transform.md" "77469df641fe8ceb22d052d8698db8fa" "site/built/03-transform.md" "2024-03-08"
 "episodes/04-motion.md" "c2642d107deb0093d78e111d359bd16f" "site/built/04-motion.md" "2024-03-08"
 "episodes/05-select.md" "600928a8a4997755e32c8755cfeb31fd" "site/built/05-select.md" "2024-03-08"
-"episodes/06-join.md" "6953137fef1d92b56eb45ab790fe08d4" "site/built/06-join.md" "2024-03-08"
+"episodes/06-join.md" "9b19db10b8e0f95e622be96fd6e54025" "site/built/06-join.md" "2024-03-08"
 "episodes/07-photo.md" "1cc618a02e5cf609052e83abaebf0094" "site/built/07-photo.md" "2024-03-08"
 "episodes/08-plot.md" "abae0965c1415da07a22c13593bbfe4f" "site/built/08-plot.md" "2024-03-08"
 "instructors/calculating_MIST_isochrone.md" "3201f3ca13dc11bbef74a7d24a433362" "site/built/calculating_MIST_isochrone.md" "2023-05-15"