when do we use triggers instead of workflows and process builder for automation in salesforce? what is the purpose of triggers . please help with some scenarios.
Here we have some of the blogs where you can go through it that will understand you better.
For 1st question: https://intellipaat.com/blog/tutorial/salesforce-tutorial/triggers-in-salesforce/
For 2nd question: https://intellipaat.com/blog/tutorial/salesforce-tutorial/process-builder/
If you wish to learn more about Salesforce, visit Salesforce tutorial and Salesforce Certification by Intellipaat.