diff --git a/LICENSE b/LICENSE
index ba1e185..37eddb3 100644
--- a/LICENSE
+++ b/LICENSE
@@ -2,3 +2,5 @@ Individual copyrights are mostly stated in each file.
 
 Connectivity workshop and network code (c) 2013 @whaleygeek
 Hardware workshop and servo/GPIO code (c) 2013 Dr James Dalley
+TKinter workshop and code (c) 2013 Mr James Dent.
+
diff --git a/code/backup/pythagoras.gif b/code/backup/pythagoras.gif
new file mode 100644
index 0000000..c299c07
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diff --git a/code/backup/pythagoras.py b/code/backup/pythagoras.py
new file mode 100644
index 0000000..fd9e6f8
--- /dev/null
+++ b/code/backup/pythagoras.py
@@ -0,0 +1,73 @@
+#Version 1.2    James Dent, Frank Everest, David Whale, 8th December 2013
+#This program is adapted from James Dent's tkinter flashcards.
+
+from tkinter import *
+import math
+
+def calcHypotenuse(*ignore):
+    a = value_a.get()   #store value from input
+    b = value_b.get()   #store value from input
+    asquared = float(a) * float(a)
+    bsquared = float(b) * float(b)
+    csquared = asquared + bsquared
+    c = math.sqrt(csquared)
+    #Send the result to the screen:
+    txt = Label(app, text="Hypotenuse is " + str(c))
+    txt.grid(row=8, sticky=W)
+
+root = Tk()
+root.resizable(0,0)         #stop window from being resizedroot = Tk()
+app = Frame(root)	    #create a frame
+app.grid()		    #use a grid to layout the frame
+root.title("Pythagoras")    #Graphical User Interface (GUI) title.
+root.geometry("400x600")    #set GUI size
+
+# create a Label and import the picture 
+picture = Label(app)
+picture.grid(row=0, columnspan=3, sticky=W)
+
+# 'sticky = W' means left aligned (West)
+pythagoras = PhotoImage(file="pythagoras.gif")
+
+#needs to be in same directory
+picture["image"] = pythagoras
+
+
+#create a label and display text on four lines:
+lbl = Label(app, text="this will calculate the length")
+lbl.grid(row=1, columnspan=3, sticky=W)
+lbl = Label(app, text="of the hypotenuse (c)")
+lbl.grid(row=2, columnspan=3, sticky=W)
+lbl = Label(app, text="for a right-angled triangle")
+lbl.grid(row=3, columnspan=3, sticky=W)
+lbl = Label(app, text="with sides (a) and (b).")
+lbl.grid(row=4, columnspan=3, sticky=W)
+
+#create an on-screen button for the side a:
+lbl = Label(app, text="Enter length of side a:")
+lbl.grid(row=5, columnspan=3, sticky=W)
+#get the value typed in:
+value_a = Entry(app, width=10)
+value_a.grid(row=5, column=10, sticky=W)
+
+#create an on-screen button for the side b:
+lbl = Label(app, text="Enter length of side b:")
+lbl.grid(row=6, columnspan=3, sticky=W)
+#get the value typed in:
+value_b = Entry(app, width=10)
+value_b.grid(row=6, column=10, sticky=W)
+
+def ledON():
+  GPIO.output(LED, False) # on, see card 12
+
+def ledOFF():
+  GPIO.output(LED, True) # off, see card 12
+
+onBtn = Button(app, text='turn it on', command=ledON)
+onBtn.grid(row=8, column=1, sticky=W)
+offBtn = Button(app, text='turn it off', command=ledOFF)
+offBtn.grid(row=8, column=2, sticky=W)
+
+calc = Button(app, text="Calculate!", command=calcHypotenuse)
+calc.grid(row=7, column=1, sticky=W)
+root.mainloop()
diff --git a/docs/Tkinter-Flashcards.pdf b/docs/Tkinter-Flashcards.pdf
new file mode 100644
index 0000000..989755e
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