What is the difference between an assignee field, a watchers' field and a people custom field?

[Valentin Dragin]

Currently there is an issue I am facing on my project regarding the fact that assignee field is not enough since there is almost always more than one person involved in the process of development. 

The watchers' field is too general because everybody receives a ton of such notifications and they are not differentiated between the important ones and just noise. 

Lately I have been introduced to the people field. Could anyone tell me please the difference between the assignee and the people field? What is your experience with the people field?

[Stefan Grob]

Hi @Valentin Dragin - this is an important question, I am asking myself too, how I can use the field "people". For me it would be useful, if the persons mentioned in the people-field would also be listed in the main-filter on the kanban-board. there you can only filter the assignees I think. Or is there a possibility to pick multiple users/assignees/people for a task and make them available in the filter of the kanban-board? thanks for an answer to this one.

[Aiden Marriott]

Hi @Valentin Dragin This is a "next gen" only concept I think (although there are user-picker fields for classic projects).  Details available here: 

https://support.atlassian.com/jira-software-cloud/docs/available-custom-fields-for-next-gen-projects/

[Valentin Dragin]

Hi @Aiden Marriott I know that this is a "next gen" concept. Before asking this question I have already read the website you sent. The information on that page barely has any details. 
I'm afraid your comment does not help. 

[Aiden Marriott]

If you have read that page I am confused as to what you are asking.  Its a custom field that holds one or more Jira users.  Assignee is a system field limited to one person.   If you create a custom field rather than use the system field it won't be in any notification scheme by default.... not much else to it.