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Digital logic

Propositional or boolean logic:
Basically logics are of two types; propositional logic and predicate logic. Proposition is an assertion which is either true or false but cannot be both at same time.
Eg:
1. 3+4=7
2. 19 is a prime number
3. Earth is rectangular in shape

In this statement 1 and 2 are proposition but 3rd is not bcoz it's false statement. This is assertion not proposition and this is called linear paradox.
Basic logic operations on proposition:
1.)Conjunction: Let p and q are two propositions.Conjunction is described by a word " and" . Truth table for and gate is:
  2. Disjunction: it is described by "or" . Truth table for or is:
3. Negation: It is represented by tilde ~. Truth table is:
4. Implication: Represented by =>.                     


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