Finite automata are the simplest machines for recognizing patterns, consisting of states that determine if an input string is accepted or rejected. The formal definition includes a 5-tuple comprising states, input symbols, initial and final states, and a transition function. Differences between deterministic finite automata (DFA) and non-deterministic finite automata (NFA) highlight that all DFAs are NFAs, but the reverse is not true, with DFAs commonly used in lexical analysis.

1. NAME: FIADUZ ZAMAN
STUDENT CODE: BWU/BTA/21/101
COURSE NAME: FORMAL LANGUAGE & AUTOMATA
THEORY
COURSE CODE: PCC-CSM404

2. FINITE AUTOMATA

3. WHAT IS FINITE AUTOMATA ?
• Finite Automata(FA) is the simplest machine to recognize
patterns.
• At the time of transition, the automata can either move to
the next state or stay in the same state.
• Finite automata have two states, Accept state or Reject state.
When the input string is processed successfully, and the
automata reached its final state, then it will accept.

4. FORMAL DEFINITION OF FINITE AUTOMATA
A finite automaton is a collection of 5-tuple (Q, ∑, δ, q0,
F), where:
• Q: finite set of states
• ∑: finite set of the input symbol
• q0: initial state
• F: final state
• δ: Transition function

5. TRANSISON DIAGRAM
0 1 1
0
1
q1 q2 qf
Here,
•{0,1}: Inputs
•q1: Initial state
•q2: Intermediate
state
•qf: Final state
start

6. TRANSITON TABLE
0 1
1
0
1
q1 q2 qf
start
STATES 0 1
→ q1 q1 q2
q2 qf q2
qf - qf

7. TYPES OF FINITE AUTOMATA
FINITE AUTOMATA
DFA NFA

8. DFA & NFA
Some important points about DFA and NFA:
i. Every DFA is NFA, but NFA is not DFA.
ii. There can be multiple final states in both NFA and
DFA.
iii. DFA is used in Lexical Analysis in Compiler.
iv. NFA is more of a theoretical concept.

9. REFERENCES
• JAVATPOINT
https://www.javatpoint.com/finite-automata
• TUTORIALSPOINT
https://www.tutorialspoint.com/what-is-finite-automata

10. THANK YOU