Logic
Basic Understanding of Logic
- Logic, in computer science, is concerned with how we make decisions based on multiple conditions.
- Processes in a computer, like calculations and data processing, are performed in a logical sequence.
- Understanding the basics of logic is crucial to writing well-structured code.
Boolean Logic
- Boolean Logic only has two possible values: true or false.
- It’s named after mathematician George Boole, who set the groundwork for modern digital computer logic.
- In programming, Boolean logic corresponds to the
yes/no
oron/off
principle.
Logic Gates
- Logic Gates are used to implement Boolean logic in hardware.
- The basic types are: AND, OR and NOT.
- ‘AND’ output true when both inputs are true.
- ‘OR’ output true when at least one input is true.
- ‘NOT’ output the opposite of the input.
Other Logic Gates
- There are also combined gates such as: NOR, NAND, XOR and XNOR.
- ‘NOR’ is the opposite of the OR gate - it outputs true only when both inputs are false.
- ‘NAND’ is the opposite of the AND gate - it outputs true unless both inputs are true.
- ‘XOR’ or exclusive OR only outputs true when the inputs are different.
- ‘XNOR’ or exclusive NOR only outputs true when the inputs are the same.
Truth Tables
- A Truth Table is a mathematical table used in logic to calculate the results of a logic function for each possible combination of input values.
- Understanding truth tables is vital for understanding how logic gates work.
Binary Logic
- Binary Logic deals with variables that take on just two values: 0 and 1, which also correspond to logic values false and true respectively.
- Binary logic is the heart of digital electronics and computer science.
Logical Operators
- Logical Operators are used to manipulate true or false values.
- Common ones are: AND, OR, NOT, NAND, NOR, XOR, and XNOR.
- These are used to specify multiple conditions within a sequence of code.