diff --git a/Hayet_Classwork/cp b/Hayet_Classwork/cp
new file mode 100755
index 0000000..11151d1
Binary files /dev/null and b/Hayet_Classwork/cp differ
diff --git a/Hayet_Classwork/cp.c b/Hayet_Classwork/cp.c
new file mode 100644
index 0000000..4ac8ca7
--- /dev/null
+++ b/Hayet_Classwork/cp.c
@@ -0,0 +1,18 @@
+#include <stdio.h>
+
+typedef unsigned char BYTE;
+int main(int argc, char *argv[])
+{
+	FILE *src = fopen(argv[1], "rb");
+	FILE *dst = fopen(argv[2], "wb");
+
+	BYTE b;
+
+	while (fread(&b, sizeof(b), 1, src) != 0)
+	{
+		fwrite(&b, sizeof(b), 1, dst);
+	}
+
+	fclose(dst);
+	fclose(src);
+}
diff --git a/Hayet_Classwork/cp.csv b/Hayet_Classwork/cp.csv
new file mode 100644
index 0000000..68c036b
--- /dev/null
+++ b/Hayet_Classwork/cp.csv
@@ -0,0 +1,2 @@
+Hayet, 77666327
+Munna, 59950786
diff --git a/Hayet_Classwork/phonebook b/Hayet_Classwork/phonebook
new file mode 100755
index 0000000..a8f9111
Binary files /dev/null and b/Hayet_Classwork/phonebook differ
diff --git a/Hayet_Classwork/phonebook.c b/Hayet_Classwork/phonebook.c
new file mode 100644
index 0000000..97503fb
--- /dev/null
+++ b/Hayet_Classwork/phonebook.c
@@ -0,0 +1,20 @@
+#include <cs50.h>
+#include <stdio.h>
+#include <string.h>
+
+int main(void)
+{
+	// FILE here calls FILE function from stdio.h & "a" using for apend.
+	FILE *file = fopen("phonebook.csv", "a");
+	if (file == NULL)
+	{
+		return 1;
+	}
+	char *name = get_string("Name: ");
+	char *number = get_string("Number: ");
+
+	fprintf(file, "%s, %s\n", name, number);
+
+	fclose(file);
+	return 0;
+}
diff --git a/Hayet_Classwork/phonebook.csv b/Hayet_Classwork/phonebook.csv
new file mode 100644
index 0000000..68c036b
--- /dev/null
+++ b/Hayet_Classwork/phonebook.csv
@@ -0,0 +1,2 @@
+Hayet, 77666327
+Munna, 59950786
diff --git a/address b/address
new file mode 100755
index 0000000..2aefb57
Binary files /dev/null and b/address differ
diff --git a/address.c b/address.c
new file mode 100644
index 0000000..fd53594
--- /dev/null
+++ b/address.c
@@ -0,0 +1,9 @@
+#include <stdio.h>
+
+int main(void)
+
+{
+	int n = 50;
+	int *p = &n;
+	printf("%p\n", p);
+}
diff --git a/example1.c b/example1.c
new file mode 100644
index 0000000..1ef9984
--- /dev/null
+++ b/example1.c
@@ -0,0 +1,7 @@
+const iunt capacity = 50;
+
+typedef struct 
+{
+	person people[CAPACITY]
+	int size;
+} stack;
diff --git a/garbage b/garbage
new file mode 100755
index 0000000..75de09c
Binary files /dev/null and b/garbage differ
diff --git a/garbage.c b/garbage.c
new file mode 100644
index 0000000..79226c5
--- /dev/null
+++ b/garbage.c
@@ -0,0 +1,10 @@
+#include <stdio.h>
+
+int main(void)
+{
+	int scores[1024];
+	for (int i =0; i < 1024; i++)
+	{
+		printf("%i\n", scores[i]);
+	}
+}
diff --git a/isiah/learning-area b/isiah/learning-area
new file mode 160000
index 0000000..31b3ff0
--- /dev/null
+++ b/isiah/learning-area
@@ -0,0 +1 @@
+Subproject commit 31b3ff0a62eb38659ef8eed6e1c9e9d69cb7ea2d
diff --git a/memory b/memory
new file mode 100755
index 0000000..1b38b1b
Binary files /dev/null and b/memory differ
diff --git a/memory.c b/memory.c
new file mode 100644
index 0000000..9830c9f
--- /dev/null
+++ b/memory.c
@@ -0,0 +1,17 @@
+// Demonstrates memory error via valgrind
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void)
+{
+	int *x = malloc(3 * sizeof(int));
+	{
+		return 1;
+	}	
+	x[0] = 72;
+	x[1] = 73;
+	x[2] = 33;
+	free(x);
+	return 0;
+}
diff --git a/note.txt b/note.txt
index b451de4..3b6a174 100644
--- a/note.txt
+++ b/note.txt
@@ -20,3 +20,6 @@ vi .gitignore
 - libcs50/
 - a.out
 
+
+// Memory Check
+valgrind is an arcane software often useful for testing memory.