What would we do without them?
+---+--+---+ +---+---*---+ __
1A |1 +--+ 14| VCC | A | B |/Y | /Y = AB
1B |2 13| 4B +===+===*===+
/1Y |3 12| 4A | 0 | 0 | 1 |
2A |4 7400 11| /4Y | 0 | 1 | 1 |
2B |5 10| 3B | 1 | 0 | 1 |
/2Y |6 9| 3A | 1 | 1 | 0 |
GND |7 8| /3Y +---+---*---+
+----------+
+---+--+---+ +---+---*---+ __
/1Y |1 +--+ 14| VCC | A | B |/Y | /Y = AB
1A |2 13| /4Y +===+===*===+
1B |3 12| 4B | 0 | 0 | Z |
/2Y |4 7401 11| 4A | 0 | 1 | Z |
2A |5 10| /3Y | 1 | 0 | Z |
2B |6 9| 3B | 1 | 1 | 0 |
GND |7 8| 3A +---+---*---+
+----------+
+---+--+---+ +---+---*---+ ___
/1Y |1 +--+ 14| VCC | A | B |/Y | /Y = A+B
1A |2 13| /4Y +===+===*===+
1B |3 12| 4B | 0 | 0 | 1 |
/2Y |4 7402 11| 4A | 0 | 1 | 0 |
2A |5 10| /3Y | 1 | 0 | 0 |
2B |6 9| 3B | 1 | 1 | 0 |
GND |7 8| 3A +---+---*---+
+----------+
+---+--+---+ +---+---*---+ __
1A |1 +--+ 14| VCC | A | B |/Y | /Y = AB
1B |2 13| 4B +===+===*===+
/1Y |3 12| 4A | 0 | 0 | Z |
2A |4 7403 11| /4Y | 0 | 1 | Z |
2B |5 10| 3B | 1 | 0 | Z |
/2Y |6 9| 3A | 1 | 1 | 0 |
GND |7 8| /3Y +---+---*---+
+----------+
+---+--+---+ +---*---+ _
1A |1 +--+ 14| VCC | A |/Y | /Y = A
/1Y |2 13| 6A +===*===+
2A |3 12| /6Y | 0 | 1 |
/2Y |4 7404 11| 5A | 1 | 0 |
3A |5 10| /5Y +---*---+
/3Y |6 9| 4A
GND |7 8| /4Y
+----------+
+---+--+---+ +---*---+ _
1A |1 +--+ 14| VCC | A |/Y | /Y = A
/1Y |2 13| 6A +===*===+
2A |3 12| /6Y | 0 | Z |
/2Y |4 7405 11| 5A | 1 | 0 |
3A |5 10| /5Y +---*---+
/3Y |6 9| 4A
GND |7 8| /4Y
+----------+
+---+--+---+ +---*---+ _
1A |1 +--+ 14| VCC | A |/Y | /Y = A
/1Y |2 13| 6A +===*===+
2A |3 12| /6Y | 0 | Z |
/2Y |4 7406 11| 5A | 1 | 0 |
3A |5 10| /5Y +---*---+
/3Y |6 9| 4A
GND |7 8| /4Y
+----------+
+---+--+---+ +---*---+
1A |1 +--+ 14| VCC | A | Y | Y = A
1Y |2 13| 6A +===*===+
2A |3 12| 6Y | 0 | 0 |
2Y |4 7407 11| 5A | 1 | Z |
3A |5 10| 5Y +---*---+
3Y |6 9| 4A
GND |7 8| 4Y
+----------+
+---+--+---+ +---+---*---+
1A |1 +--+ 14| VCC | A | B | Y | Y = AB
1B |2 13| 4B +===+===*===+
1Y |3 12| 4A | 0 | 0 | 0 |
2A |4 7408 11| 4Y | 0 | 1 | 0 |
2B |5 10| 3B | 1 | 0 | 0 |
2Y |6 9| 3A | 1 | 1 | 1 |
GND |7 8| 3Y +---+---*---+
+----------+
+---+--+---+ +---+---*---+
1A |1 +--+ 14| VCC | A | B | Y | Y = AB
1B |2 13| 4B +===+===*===+
1Y |3 12| 4A | 0 | 0 | 0 |
2A |4 7409 11| 4Y | 0 | 1 | 0 |
2B |5 10| 3B | 1 | 0 | 0 |
2Y |6 9| 3A | 1 | 1 | Z |
GND |7 8| 3Y +---+---*---+
+----------+
+---+--+---+ +---+---+---*---+ ___
1A |1 +--+ 14| VCC | A | B | C |/Y | /Y = ABC
1B |2 13| 1C +===+===+===*===+
2A |3 12| /1Y | 0 | X | X | 1 |
2B |4 7410 11| 3C | 1 | 0 | X | 1 |
2C |5 10| 3B | 1 | 1 | 0 | 1 |
/2Y |6 9| 3A | 1 | 1 | 1 | 0 |
GND |7 8| /3Y +---+---+---*---+
+----------+
+---+--+---+ +---+---+---*---+
1A |1 +--+ 14| VCC | A | B | C | Y | Y = ABC
1B |2 13| 1C +===+===+===*===+
2A |3 12| 1Y | 0 | X | X | 0 |
2B |4 7411 11| 3C | 1 | 0 | X | 0 |
2C |5 10| 3B | 1 | 1 | 0 | 0 |
2Y |6 9| 3A | 1 | 1 | 1 | 1 |
GND |7 8| 3Y +---+---+---*---+
+----------+
+---+--+---+ +---+---+---*---+ ___
1A |1 +--+ 14| VCC | A | B | C |/Y | /Y = ABC
1B |2 13| 1C +===+===+===*===+
2A |3 12| /1Y | 0 | X | X | Z |
2B |4 7410 11| 3C | 1 | 0 | X | Z |
2C |5 10| 3B | 1 | 1 | 0 | Z |
/2Y |6 9| 3A | 1 | 1 | 1 | 0 |
GND |7 8| /3Y +---+---+---*---+
+----------+
+---+--+---+ +---+---+---+---*---+ ____
1A |1 +--+ 14| VCC | A | B | C | D |/Y | /Y = ABCD
1B |2 13| 2D +===+===+===+===*===+
|3 12| 2C | 0 | X | X | X | 1 |
1C |4 7413 11| | 1 | 0 | X | X | 1 |
1D |5 10| 2B | 1 | 1 | 0 | X | 1 |
/1Y |6 9| 2A | 1 | 1 | 1 | 0 | 1 |
GND |7 8| /2Y | 1 | 1 | 1 | 1 | 0 |
+----------+ +---+---+---+---*---+
+---+--+---+ +---*---+ _
1A |1 +--+ 14| VCC | A |/Y | /Y = A
/1Y |2 13| 6A +===*===+
2A |3 12| /6Y | 0 | 1 |
/2Y |4 7414 11| 5A | 1 | 0 |
3A |5 10| /5Y +---*---+
/3Y |6 9| 4A
GND |7 8| /4Y
+----------+
+---+--+---+ +---+---+---*---+
1A |1 +--+ 14| VCC | A | B | C | Y | Y = ABC
1B |2 13| 1C +===+===+===*===+
2A |3 12| 1Y | 0 | X | X | 0 |
2B |4 7415 11| 3C | 1 | 0 | X | 0 |
2C |5 10| 3B | 1 | 1 | 0 | 0 |
2Y |6 9| 3A | 1 | 1 | 1 | Z |
GND |7 8| 3Y +---+---+---*---+
+----------+
+---+--+---+ +---*---+ _
1A |1 +--+ 14| VCC | A |/Y | /Y = A
/1Y |2 13| 6A +===*===+
2A |3 12| /6Y | 0 | Z |
/2Y |4 7416 11| 5A | 1 | 0 |
3A |5 10| /5Y +---*---+
/3Y |6 9| 4A
GND |7 8| /4Y
+----------+
+---+--+---+ +---*---+
1A |1 +--+ 14| VCC | A | Y | Y = A
1Y |2 13| 6A +===*===+
2A |3 12| 6Y | 0 | 0 |
2Y |4 7417 11| 5A | 1 | Z |
3A |5 10| 5Y +---*---+
3Y |6 9| 4A
GND |7 8| 4Y
+----------+
+---+--+---+ +---+---+---+---*---+ ____
1A |1 +--+ 14| VCC | A | B | C | D |/Y | /Y = ABCD
1B |2 13| 2D +===+===+===+===*===+
|3 12| 2C | 0 | X | X | X | 1 |
1C |4 7418 11| | 1 | 0 | X | X | 1 |
1D |5 10| 2B | 1 | 1 | 0 | X | 1 |
/1Y |6 9| 2A | 1 | 1 | 1 | 0 | 1 |
GND |7 8| /2Y | 1 | 1 | 1 | 1 | 0 |
+----------+ +---+---+---+---*---+
+---+--+---+ +---*---+ _
1A |1 +--+ 14| VCC | A |/Y | /Y = A
/1Y |2 13| 6A +===*===+
2A |3 12| /6Y | 0 | 1 |
/2Y |4 7414 11| 5A | 1 | 0 |
3A |5 10| /5Y +---*---+
/3Y |6 9| 4A
GND |7 8| /4Y
+----------+
+---+--+---+ +---+---+---+---*---+ ____
1A |1 +--+ 14| VCC | A | B | C | D |/Y | /Y = ABCD
1B |2 13| 2D +===+===+===+===*===+
|3 12| 2C | 0 | X | X | X | 1 |
1C |4 7420 11| | 1 | 0 | X | X | 1 |
1D |5 10| 2B | 1 | 1 | 0 | X | 1 |
/1Y |6 9| 2A | 1 | 1 | 1 | 0 | 1 |
GND |7 8| /2Y | 1 | 1 | 1 | 1 | 0 |
+----------+ +---+---+---+---*---+
+---+--+---+ +---+---+---+---*---+
1A |1 +--+ 14| VCC | A | B | C | D | Y | Y = ABCD
1B |2 13| 2D +===+===+===+===*===+
|3 12| 2C | 0 | X | X | X | 0 |
1C |4 7421 11| | 1 | 0 | X | X | 0 |
1D |5 10| 2B | 1 | 1 | 0 | X | 0 |
1Y |6 9| 2A | 1 | 1 | 1 | 0 | 0 |
GND |7 8| 2Y | 1 | 1 | 1 | 1 | 1 |
+----------+ +---+---+---+---*---+
+---+--+---+ +---+---+---+---*---+ ____
1A |1 +--+ 14| VCC | A | B | C | D |/Y | /Y = ABCD
1B |2 13| 2D +===+===+===+===*===+
|3 12| 2C | 0 | X | X | X | Z |
1C |4 7422 11| | 1 | 0 | X | X | Z |
1D |5 10| 2B | 1 | 1 | 0 | X | Z |
/1Y |6 9| 2A | 1 | 1 | 1 | 0 | Z |
GND |7 8| /2Y | 1 | 1 | 1 | 1 | 0 |
+----------+ +---+---+---+---*---+
+---+--+---+ +---+---*---+ __
1A |1 +--+ 14| VCC | A | B |/Y | /Y = AB
1B |2 13| 4B +===+===*===+
/1Y |3 12| 4A | 0 | 0 | 1 |
2A |4 7424 11| /4Y | 0 | 1 | 1 |
2B |5 10| 3B | 1 | 0 | 1 |
/2Y |6 9| 3A | 1 | 1 | 0 |
GND |7 8| /3Y +---+---*---+
+----------+
+---+--+---+ __________
1A |1 +--+ 14| VCC Y = G(A+B+C+D)
1B |2 13| 2D
1G |3 12| 2C
1C |4 7425 11| 2G
1D |5 10| 2B
/1Y |6 9| 2A
GND |7 8| /2Y
+----------+
+---+--+---+ +---+---*---+ __
1A |1 +--+ 14| VCC | A | B |/Y | /Y = AB
1B |2 13| 4B +===+===*===+
/1Y |3 12| 4A | 0 | 0 | Z |
2A |4 7426 11| /4Y | 0 | 1 | Z |
2B |5 10| 3B | 1 | 0 | Z |
/2Y |6 9| 3A | 1 | 1 | 0 |
GND |7 8| /3Y +---+---*---+
+----------+
+---+--+---+ +---+---+---*---+ _____
1A |1 +--+ 14| VCC | A | B | C |/Y | /Y = A+B+C
1B |2 13| 1C +===+===+===*===+
2A |3 12| /1Y | 0 | 0 | 0 | 1 |
2B |4 7427 11| 3C | 0 | 0 | 1 | 0 |
2C |5 10| 3B | 0 | 1 | X | 0 |
/2Y |6 9| 3A | 1 | X | X | 0 |
GND |7 8| /3Y +---+---+---*---+
+----------+
+---+--+---+ +---+---*---+ ___
/1Y |1 +--+ 14| VCC | A | B |/Y | /Y = A+B
1A |2 13| /4Y +===+===*===+
1B |3 12| 4B | 0 | 0 | 1 |
/2Y |4 7428 11| 4A | 0 | 1 | 0 |
2A |5 10| /3Y | 1 | 0 | 0 |
2B |6 9| 3B | 1 | 1 | 0 |
GND |7 8| 3A +---+---*---+
+----------+
+---+--+---+ ________
A |1 +--+ 14| VCC /Y = ABCDEFGH
B |2 13|
C |3 12| H
D |4 7430 11| G
E |5 10|
F |6 9|
GND |7 8| /Y
+----------+
+---+--+---+ _ _____
1A |1 +--+ 16| VCC /1Y=1A /4Y=4A.4B
/1Y |2 15| 6A
2A |3 14| /6Y 2Y=2A 5Y=5A
2Y |4 13| 5A _____ _
3A |5 7431 12| 5Y /3Y=3A.3B /6Y=6A
3B |6 11| 4B
/3Y |7 10| 4A
GND |8 9| /4Y
+----------+
+---+--+---+ +---+---*---+
1A |1 +--+ 14| VCC | A | B | Y | Y = A+B
1B |2 13| 4B +===+===*===+
1Y |3 12| 4A | 0 | 0 | 0 |
2A |4 7432 11| 4Y | 0 | 1 | 1 |
2B |5 10| 3B | 1 | 0 | 1 |
2Y |6 9| 3A | 1 | 1 | 1 |
GND |7 8| 3Y +---+---*---+
+----------+
+---+--+---+ +---+---*---+ ___
/1Y |1 +--+ 14| VCC | A | B |/Y | /Y = A+B
1A |2 13| /4Y +===+===*===+
1B |3 12| 4B | 0 | 0 | Z |
/2Y |4 7433 11| 4A | 0 | 1 | 0 |
2A |5 10| /3Y | 1 | 0 | 0 |
2B |6 9| 3B | 1 | 1 | 0 |
GND |7 8| 3A +---+---*---+
+----------+
+---+--+---+ +---+---*---+ __
1A |1 +--+ 14| VCC | A | B |/Y | /Y = AB
1B |2 13| 4B +===+===*===+
/1Y |3 12| 4A | 0 | 0 | 1 |
2A |4 7437 11| /4Y | 0 | 1 | 1 |
2B |5 10| 3B | 1 | 0 | 1 |
/2Y |6 9| 3A | 1 | 1 | 0 |
GND |7 8| /3Y +---+---*---+
+----------+
+---+--+---+ +---+---*---+ __
1A |1 +--+ 14| VCC | A | B |/Y | /Y = AB
1B |2 13| 4B +===+===*===+
/1Y |3 12| 4A | 0 | 0 | Z |
2A |4 7438 11| /4Y | 0 | 1 | Z |
2B |5 10| 3B | 1 | 0 | Z |
/2Y |6 9| 3A | 1 | 1 | 0 |
GND |7 8| /3Y +---+---*---+
+----------+
+---+--+---+ +---+---+---+---*---+ ____
1A |1 +--+ 14| VCC | A | B | C | D |/Y | /Y = ABCD
1B |2 13| 2D +===+===+===+===*===+
|3 12| 2C | 0 | X | X | X | 1 |
1C |4 7440 11| | 1 | 0 | X | X | 1 |
1D |5 10| 2B | 1 | 1 | 0 | X | 1 |
/1Y |6 9| 2A | 1 | 1 | 1 | 0 | 1 |
GND |7 8| /2Y | 1 | 1 | 1 | 1 | 0 |
+----------+ +---+---+---+---*---+
+---+--+---+ +---+---+---+---*---+---+---+---+
/Y0 |1 +--+ 16| VCC | S3| S2| S1| S0|/Y0|/Y1|...|/Y9|
/Y1 |2 15| S0 +===+===+===+===*===+===+===+===+
/Y2 |3 14| S1 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 |
/Y3 |4 13| S2 | 0 | 0 | 0 | 1 | 1 | 0 | 1 | 1 |
/Y4 |5 7442 12| S3 | . | . | . | . | 1 | 1 | . | 1 |
/Y5 |6 11| /Y9 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 0 |
/Y6 |7 10| /Y8 | 1 | 0 | 1 | X | 1 | 1 | 1 | 1 |
GND |8 9| /Y7 | 1 | 1 | X | X | 1 | 1 | 1 | 1 |
+----------+ +---+---+---+---*---+---+---+---+
+---+--+---+
A1 |1 +--+ 16| VCC
A2 |2 15| /YF
/LT |3 14| /YG
/RBO |4 13| /YA
/RBI |5 7447 12| /YB
A3 |6 11| /YC
A0 |7 10| /YD
GND |8 9| /YE
+----------+
+---+--+---+
A1 |1 +--+ 16| VCC
A2 |2 15| YF
/LT |3 14| YG
/RBO |4 13| YA
/RBI |5 7448 12| YB
A3 |6 11| YC
A0 |7 10| YD
GND |8 9| YE
+----------+