How do I write data to a tag through an events tag?

Good night. I’m new to Ignition and while I’m studying I have a lot of questions and I think a lot of them are pretty simple. I already got the application made, it wasn’t me who developed it. So, my question is: for example, According to the image below the count_shift tag writing production data from a certain machine, count_per_minute is writing production data per minute from the same machine. my biggest question is: are these tags collecting this information through the zShiftCount tag events tag? if not, where is this information coming from that these tags are collecting? I also ask that if possible, explain to me a little about the programming of the zShiftCount tag events. thanks!!!