diff --git a/docs/generate_docs.sh b/docs/generate_docs.sh
index 0bd309e..19aaf95 100755
--- a/docs/generate_docs.sh
+++ b/docs/generate_docs.sh
@@ -4,6 +4,9 @@
 # TODO: create options for generating different file types (pdf, html or utf8 to console/file).
 # Prompt user at the start for what type they want.
 
+# Specify the file paths, in the order where they should be built.
+filepaths=('nodes/single_node.h.ms' 'nodes/double_node.h.ms' 'nodes/tree_node.h.ms' 'strings/strzcpy.ms')
+
 # Prompt the user for the option they want (pdf/html/utf8).
 echo "Please choose an output option: pdf, html or utf8."
 select choice in "pdf" "html" "utf8"; do
@@ -28,9 +31,6 @@ done
 # Get the initial root.
 root_directory=$(pwd)
 
-# Specify the file paths, in the order where they should be built.
-filepaths=('nodes/single_node.h.ms')
-
 # Loop over the paths: change directory, build, go back up to the root directory.
 for i in $filepaths; do
 	# Get the current directory that we should change into, from the current array variable.
@@ -49,7 +49,7 @@ for i in $filepaths; do
 	# Create the output file.
 	touch $output_file
 	# Generate docs.
-	groff -ms -Tpdf $input_file > $output_file
+	groff -ms -T$filetype $input_file > $output_file
 
 	# Go back up to the root.
 	cd $root_directory
diff --git a/progress_and_notes b/progress_and_notes
index 7f353e3..c05f5bd 100644
--- a/progress_and_notes
+++ b/progress_and_notes
@@ -1,4 +1,4 @@
-Everything is implemented and tested.
+Make sure everything is implemented and tested.
 TODO: imlement better tests, maybe even use a testing framework?
 
 Future goals:
@@ -6,4 +6,26 @@ Implement more data structures, such as hash tables, hash maps, more trees.
 Implement algorithms to go with said DSs.
 Implement generic algorithms (start from sort and search).
 
-Write documentation - probably using groff to be able to make man pages.
+Write documentation.
+
+Currently implemented:
+Single node.
+Double linked node.
+Tree node.
+Linked list.
+Double linked list.
+Stack.
+Safe string copy (not tested - not a priority).
+Bubble Sort (not tested).
+
+To be implemented:
+Queue.
+Double-ended queue.
+Hashmap.
+Heap.
+BST - Binary Search Tree.
+AVL trees.
+Red-Black trees.
+AA Trees (?).
+Circular buffer (?).
+Array list (?).
diff --git a/sorting_algorithms/bubble_sort/bubble_sort.c b/sorting_algorithms/bubble_sort/bubble_sort.c
index 1a3524d..42e27a9 100644
--- a/sorting_algorithms/bubble_sort/bubble_sort.c
+++ b/sorting_algorithms/bubble_sort/bubble_sort.c
@@ -1,5 +1,65 @@
-/* This header defines the function for bubble sort. */
-#ifndef BUBBLE_SORT_H
-#define BUBBLE_SORT_H
-void** bubble_sort(void** array, void (*comparison_function)());
-#endif /* BUBBLE_SORT_H */
+/* This file has the implementation of the function for bubble sort. */
+/* Include guards + include statements. */
+#ifndef BUBBLE_SORT_C
+#define BUBBLE_SORT_C
+#include <string.h>
+#include "bubble_sort.h"
+#endif /* BUBBLE_SORT_C */
+
+/* Function implementation. */
+/* Note that if the comparison function is NULL, then the regular comparison operator is used <. */
+/* Note that if copy is set to 0, then the array is sorted in-place, otherwise a sorted copy
+* is what gets returned (after allocation), leaving the original intact. */
+/* Note that the comparison function should return 1 if the second argument is larger than or
+* equal to the first, otherwise zero. */
+/* The array's length should be passed in the length argument. */
+/* The function returns a NULL pointer on error, caller must check! */
+void** bubble_sort(const void** array, const void (*comparison_function)(), const int length, const int copy) {
+	/* Sanity check. */
+	if (array == NULL)
+		return NULL;
+
+	/* Local variables. */
+	int i, j;
+	void **ptr, void *tmp;
+
+	/* Check if to allocate a copy. */
+	if (copy) {
+		/* Allocate the array. */
+		ptr = (void**) malloc(length * sizeof(void*));
+
+		/* Check if the allocation failed. */
+		if (ptr == NULL)
+			return NULL;
+		/* Copy the arrays' contents. */
+		memcpy(ptr, array, length * sizeof(void*));
+	} else
+		ptr = array;
+
+	/* Sort according to ptr, and based on the employed comparison function. */
+	if (comparison_function != NULL)
+		for (i = 0; i < length; i++)
+			for (j = 0; j < length - 1; j++) {
+				/* Check if to swap. */
+				if (!comparison_function(ptr + j, ptr + j + 1)) {
+					/* Swap. */
+					tmp = ptr[j];
+					ptr[j] = ptr[j + 1];
+					ptr[j + 1] = tmp;
+				}
+			}
+	else
+		for (i = 0; i < length; i++)
+			for (j = 0; j < length; j++) {
+				/* Check if to swap. */
+				if (ptr[j] > ptr[j + 1]) {
+					/* Swap. */
+					tmp = ptr[j];
+					ptr[j] = ptr[j + 1];
+					ptr[j + 1] = tmp;
+				}
+			}
+
+	/* Return the result. */
+	return ptr;
+}
diff --git a/sorting_algorithms/bubble_sort/bubble_sort.h b/sorting_algorithms/bubble_sort/bubble_sort.h
index 1a3524d..4b14460 100644
--- a/sorting_algorithms/bubble_sort/bubble_sort.h
+++ b/sorting_algorithms/bubble_sort/bubble_sort.h
@@ -1,5 +1,5 @@
 /* This header defines the function for bubble sort. */
 #ifndef BUBBLE_SORT_H
 #define BUBBLE_SORT_H
-void** bubble_sort(void** array, void (*comparison_function)());
+void** bubble_sort(const void** array, const void (*comparison_function)(), const int length, const int copy);
 #endif /* BUBBLE_SORT_H */