Facebook question - how does someone post "via" someone else?

I see posts like "Marylou via Susan". How does that happen? Also, I sometimes see a right pointing arrow between two names(friends) in a post. How does that happen?
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You cannot post via someone else.  My guess is that they are posting from their phone.  Often you will see posts that say via iphone.  
Nope.  Phones say "blah blah via Facebook for iPhone" etc,

When you see a post "Marylou via Susan" for example, it means that Marylou was looking at Susan's profile, saw something she liked, and clicked the SHARE link below that item.  It then appeared on Marylou's profile, but is tagged as "Via" Susan.

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You choose the "share" button, then you have the option of useing "via" :)
Manoj PatilSr. Software EngineerCommented:
Hello sheana11,

When you see notifications like  "Marylou via Susan". Basically, it means that one of your friend(Marylou) has Share a Post on his wall from His friend's(Susan) Wall.

This is depend on the Privacy Setting of the Post. When you post something on your Facebook Wall, you have the options to set the Privacy Level. See Image below.
If you set the post to Public, then your friends can Share your post on their FB wall and Friend's of your Friend can Share this !!!
That's why. Facebook is Powerful Social Networking website for Spreading your Business, or Sharing your memory, Expose yourself, etc.

  Privacy setting Levels for POST
sheana11Author Commented:
Great explanations!
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