Digital Teaching Aid (DED Philippinen, 86 p.) 
Fundamental Logic Operations  Lesson 1 

Binary number system
All number systems have a base, which specifies how many digits can be used in each place count. For binary numbers the base is 2, with 0 and 1 as the only two digits. In the decimal system, the base is 10.
Decimal digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
Binary digits: 0, 1
Decimal to Binary Conversion
EX: Convert a 4 bit binary number
(100 1) into decimal.
Each digit position has specified weight, for binary numbers the position represents a power of two.
EX: Convert a 8 bit number (10010101)
into decimal
HO: Convert the following binary numbers into decimal:
101, 1100, 1110, 1000, 0110, 11001010, 01101111, 10001100
Binary to decimal conversion
EX: Convert the decimal number 138
into a binary number
HO: Convert the following decimal numbers into binary numbers:
12, 8, 127, 247, 139, 255