Explain how a line codificator works

Hi guys, I need your help. I'm working on a LINE CODIFICATOR, I've found all the code and all my project is done, but I need explain the source code and How It works.

Please, this is my final project and I have to do a sustentation, this is one of my GUIs and all the code:

Code for UNIPOLAR NRZ:

function pushbutton1_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
set(handles.uno,'string','')
set(handles.dos,'string','')
set(handles.tres,'string','')
set(handles.cuatro,'string','')
set(handles.cinco,'string','')
set(handles.seis,'string','')
set(handles.siete,'string','')
set(handles.ocho,'string','')
set(handles.nueve,'string','')
set(handles.diez,'string','')

% --- Executes on button press in pushbutton2.
function pushbutton2_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton2 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
a=str2double(get(handles.uno,'String'));
b=str2double(get(handles.dos,'String'));
c=str2double(get(handles.tres,'String'));
d=str2double(get(handles.cuatro,'String'));
e=str2double(get(handles.cinco,'String'));
f=str2double(get(handles.seis,'String'));
g=str2double(get(handles.siete,'String'));
h=str2double(get(handles.ocho,'String'));
i0=str2double(get(handles.nueve,'String'));
j0=str2double(get(handles.diez,'String'));


handles.bits=[a,b,c,d,e,f,g,h,i0,j0];
handles.cod=get(hObject,'Value');

 hold off;
        h=handles.bits;
        n=1;
        h(11)=1;
        while n<=10;
            t=n-1:0.001:n;
        if h(n) == 0
            if h(n+1)==0  
                y=(t>n);
            else
                y=(t==n);
            end
            d=plot(t,y);title('Código Unipolar NRZ');grid on
            set(d, 'Color','m')
            set(d,'LineWidth',2.5);
            hold on;
            axis([0 10 -1.5 1.5]);
        else
            if h(n+1)==0
                y=(t<n)-0*(t==n);
            else
                y=(t<n)+1*(t==n);
            end
            d=plot(t,y);title('Código Unipolar NRZ');grid on;
            set(d, 'Color','g')
            set(d,'LineWidth',2.5);
            hold on;
            axis([0 10 -1.5 1.5]);
        end
        n=n+1;
        end