

Global activity overview
Activity Monitor tracks all user activity on your blog or network. The activities can be viewed in global table showing activities on the whole network, or locally for just the blog you are currently viewing. The activites can be filtered so that only specific blogs / hooks / IPs / users are displayed.
Monitored actions include (not exhaustive):
The logged information consists of:
The Activity Monitor has a git repository.
There are several ways for people to break in to your WordPress installation, or cause trouble by DDOS. Here are some tips on how to use the Activity Monitor and its plugins to help detect problems:
See the developer documentation for relevant info on how to create custom hooks.