PeopleSoft Common Question:

Field edit can be used to locally check the syntactial errrors made by end user( mostly). It can be used for conplex checking operations too but rarely.

Save edit is used to check the logical existance or invalid datta inputs.It can be used for conplex checking operations.

Example if a broker becomes ineffective after a perticualr date, and if some calculations are done after that date, logic can be written in save edits to stop further processing and help the user identify another broker whose effictive date is valid for the date specified.

Field Edit peoplecode is fired when you try to change the value of a field on the page and Save Edit peoplecode is fired when you try to save the page. Both validates data but Field Edit peoplecode is used to validate the data for only that particular field which is changed and Save Edit peoplecode is used to validate all the data changes made to the fields on the page