I learning and using PLC programming best practices, it is critical to under the differnce between a Programmable Logic Controller (PLC) and Programmable Automation Controller (PAC).
We recommend reading you read the following two pages first.
PLC PAC Difference – PAC Automation Controller Defined
What is a PLC, what is a PAC?
Also just for fun, here are a couple interactive PAC training crossword puzzles on the subject.