diff --git a/04-loops.md b/04-loops.md
index fef6c29e..05a0fb38 100644
--- a/04-loops.md
+++ b/04-loops.md
@@ -138,12 +138,13 @@ Alternatively, rather than running the loop above on the command line, you can s
 
 ```
 #!/bin/bash
-# This script loops through .txt files, returns the file name, first line, and last line of the file
+# This script loops through .txt files, returns the file name,
+# first line, and last line of the file
 for file in *.txt
 do
-	echo $file
-	head -n 1 $file
-	tail -n 1 $file
+	echo "$file"
+	head -n 1 "$file"
+	tail -n 1 "$file"
 done
 ```
 
diff --git a/files/my_first_bash_script.sh b/files/my_first_bash_script.sh
index 4cd0315f..be0891d7 100644
--- a/files/my_first_bash_script.sh
+++ b/files/my_first_bash_script.sh
@@ -1,8 +1,10 @@
 #!/bin/bash
+# This script loops through .txt files, returns the
+# file name, first line, and last line of the file
 
-for filename in *.txt
+for file in *.txt
 do
- echo $filename
- head -n 5 $filename
- tail -n 5 $filename
-done
\ No newline at end of file
+ echo "$file"
+ head -n 1 "$file"
+ tail -n 1 "$file"
+done
diff --git a/md5sum.txt b/md5sum.txt
index 3e7f205d..c0e9f809 100644
--- a/md5sum.txt
+++ b/md5sum.txt
@@ -7,7 +7,7 @@
 "episodes/01-intro-shell.md" "4248552de8d7fe3f30930e93acef8436" "site/built/01-intro-shell.md" "2023-05-08"
 "episodes/02-navigating-the-filesystem.md" "c85f3b8108023b4da52d70fce13f2c43" "site/built/02-navigating-the-filesystem.md" "2024-02-23"
 "episodes/03-working-with-files-and-folders.md" "f28760ce8c1c6e3b96c8b6ccacc55772" "site/built/03-working-with-files-and-folders.md" "2024-02-23"
-"episodes/04-loops.md" "ef86d9f8b71733dea97b44a886391bdd" "site/built/04-loops.md" "2024-02-23"
+"episodes/04-loops.md" "85f66d92cc6fc1a25b0214c0d108f892" "site/built/04-loops.md" "2024-04-03"
 "episodes/05-counting-mining.md" "f61fde3e769614d41d8b22e09f38d1e7" "site/built/05-counting-mining.md" "2024-02-23"
 "episodes/06-free-text.md" "143b9518631bcf5b114d1f432e5a9c25" "site/built/06-free-text.md" "2023-05-08"
 "instructors/instructor-notes.md" "c317e03b34390725b50f49df1bf943b1" "site/built/instructor-notes.md" "2024-02-23"