Hope this makes sense. I understand bitmaps, but I have difficulty in explaining them. (So do I really understand it)

If you have 2 lamps, which condition means that they are both on?

0 & 0 = 0 -- Lamp 1 Off and Lamp 2 Off = No

0 & 1 = 0 -- Lamp 1 Off and Lamp 2 On = No

1 & 0 = 0 -- Lamp 1 On and Lamp 2 Off = No

1 & 1 = 1 -- Lamp 1 On and Lamp 2 On = Yes

Considder an 8 bit binary bitmap

All bits off = 00000000 = 0

All bits on = 11111111 = 255 (2^0 + 2^1 + 2^2 + 2^3 + 2^4 + 2^5 + 2^6 + 2^7)

Lets look at 10 & 2

00001010 (10)

00000010 ( 2)

BINARY AND 00000010 = ( 2)

Now lets look at 11 & 9

00001011 (11)

00001001 ( 9)

BINARY AND 00001001 = ( 9)

Now lets look at 11 & 3

00001011 (11)

00000011 ( 3)

BINARY AND 00000011 = ( 3)

Now, lets look at 255 & 32

11111111

00100000

BINARY AND 00100000 = 32

Now, lets look at 255 & 33

11111111

00100001

BINARY AND 00100001 = 33