isExecuting: This variable returns true if the current context for the Apex code is a trigger rather than a Visualforce page, Web service, or execute anonymous() API request.
isInsert: If the trigger executed is an insert operation, this variable returns true.
isUpdate: If the trigger executed is an update operation, this variable returns true.
isDelete: If the trigger executed is a delete action, this variable returns true.
isBefore: This variable returns true if the trigger was triggered before any records were stored.
IsAfter: This variable returns true if the trigger was triggered after all records had been saved. IsUndelete: This variable returns true if the record was retrieved from the recycle bin.
new: This variable returns a list of the updated sObject records. Only the insert, update, and undelete triggers support this.
newMap: This produces a list of Ids for the new version of the sObject records. oldMap: This returns a list of Ids for the old version of the s This variable delivers a list of all the sObject records' previous versions. This feature is only accessible in update and remove triggers. https://www.iteducationcentre.com/salesforce-training-in-pune.php
