Before you are “friends” you can only look at the other profiles you see. You can LIKE the things you see and even SHARE (below) to your timeline but, you won’t know when they post new things, you won’t see things they haven’t marked as “public” and you can’t POST on their timeline. In order to obtain these privileges you send a “friend request” and they may or may not “friend” you based on your mutual interest, pictures, friends, bio or lack thereof. If they do, you can see everything on their page, even things that aren’t public. You can also Post on their timeline and they receive the same privileges from you.
Your timeline lists everything that you post on your page in order but it alos lists things that people you “follow” post. YOUR “Posts” are permanent (until you delete them) on your page whereas things in your “timeline” (other peoples posts in addition to yours) are transient, forever being pushed off by newer posts from you and all your friends you follow. In addition, if you are “following” someone, everything they post on their page also appears on your timeline. Your timeline is NOT your profile page. The only things that are on your profile page are things you posted there and things you “share” publically. “Sharing” off your timeline posts to your page.
Your POSTS are fixed forever on your page until deleted and become transient on your friend’s timelines if they are following you.
Your Friends POSTS are fixed on their page but transient on your time line.
When you SHARE from your timeline you are taking something transient off of your timeline and posting it to your page making it permanent (until you delete it)
Remember, you can “follow” a friend or your can have a “friend” you don’t follow. I follow profiles that have interesting content and unfollow them if they are posting the same thing over and over or posting things I don’t want to see. I unfriend and unfollow them if I don’t like their content or comments.
When you friend people you further define who “you” are. Think of the Facebook world as a huge collection of bios with the profile information you put in (above). Bios with similar profile information are linked by Facebook but this is still a massive amount of bios. When you “friend”, you start to link with other bios directly (your friend) and indirectly (their friends, and friends you have in common). Your “people you may know” changes as you add more friends because “you may know” that persons (profile) friends and they may know yours. Now, fields on your profile that are in common with fields on your “friends” profiles start to further define your Fb identity. If you and your friends are all “interested” in romance, you will be solicited by publishers, other writers, writers etc. Think of it as a big Venn diagram and the targeting areas are where the rings of the diagram overlap.
1) every time you post something all your friends see your post on their timeline (if they follow you). Transient.
2) If you share something to your page, all your friends see what you shared on their timeline (if they follow you). Transient.
3) If you LIKE something your friend posted, the person who posted it will be NOTIFIED that you LIKED their post.
4) If you comment or share a post that your friend posted they will be NOTIFIED that you commented or shared their post.