Which type of program is used for functions as counters, timers, shift registers, and math operations in PLC? 

Ladder Logic Program

• Ladder Diagram (LD) logic is a graphical programming language.
• Initially programmed with simple contacts that simulated the opening and closing of relays, but later it has been expanded to include such functions as counters, timers, shift registers, and math operations.
• A timer uses the frequency of the internal clock and generates delay.
• A counter uses an external signal to count pulses.
• The register is used to store data.
• Math operations include addition, subtraction, multiplying, and dividing to calculate the sum, difference, product, and quotient of the content of word registers.