Message from member header:When you look at any members profile you can send them a message from clicking on the message buttons in their header area of their profile. See image..

Public Message:
A public message is like a public post. All members will see your message in the activity list. You can also post a message into a group.

Private Message:

Just like a regular email message you can send a friend a private message.

Activity Stream Personal:

This page is the record of all your activities throughout the site listed in chronological order. If you’re logged in, there’s a status update box before the activity stream where you can post what’s on your mind.

Filter to Show:

Everything (default)
Updates
Posts
Comments
Friendships
New Groups
Group Memberships
Group Updates

Activity Stream Mentions:

This page shows all the @ mentions you received throughout the site.

Usage: type an @ symbol before your profile name.

Filter to Show @mentions in:

Everything (default)
Updates
Posts
Comments
Friendships
New Groups
Group Memberships
Group Updates

Activity Stream Favorites:

This is a list of all the items (posts, comments, friendships, etc.) you have “favorited” in your Groups’ Activity Streams, the Sitewide Activity Stream, or even your own Personal Activity Stream.

Usage:
to add a favorite, click on the small star in the post area of each type.

Filter to Show “favorited items” in:

Everything (default)
Updates
Posts
Comments
New Groups
Group Memberships
Group Updates

Activity Stream Friends:

This panel shows all of your friends’ activities throughout the site.

Filter to Show:

Everything (default)
Updates
Posts
Comments
Friendships
New Groups
Group Memberships
Group Updates

Activity Stream Groups:

This page shows all the activities recorded in the groups you have joined.

Filter to Show:

Everything (default)
Updates
Group Updates
Group Memberships
New Groups