The Audit Log is a feed of information that tracks all the changes being made to your account and program. This allows you to view what member of your team made a change to something, what that change was, and when it was made.
The audit log has a variety of headers that will provide specific information about an action that has taken place:
Object - The item/functionality that was changed or had an action taken on it. For example if a teammate updated a trigger the object listed would be 'trigger'.
Event - The type of action that was performed on the item/functionality. This will indicated if something has been created, updated or deleted.
Field - The specific part of the item/functionality that was affected. For example if a teammate changed the name of an existing trigger, the field would list 'Name'.
Old Value - The value the item/functionality contained prior to the action taking place.
New Value - The value the item/functionality contains now.
Description - Any extra information that is pertinent to the action, for example if permissions were changed on a teammate, the teammates name would be displayed here.
Edited By - The name of the teammate or admin who enacted the change.
Edited Date - The date the change occurred.
Above the feed is a variety of search tools, these allow you to filter the results specifically by an admin/teammate or by the content of specific headers.