The exclamations points in a message tells you, you can "report this post" for example if the wording was rude or talked about things that the general members would not want to read about on this forum.
The icon saying "Edit" lets the person who wrote the post edit any spelling mistakes or just change the words.
The icon that looks like an X lets you delete your post only.
The icon that saying "Quote" lets you bring forward the message you are replying to, your message will be underneath this, if you look on the forum you will see examples of this.
The little person looking icon under the name and photo tells you, you can send that person a private message/email.
The envelope looking icon under the name and photo tell you, you can email that person.
The wording under the name and photo tell you how many posts on this forum in total that person has made e.g. our beloved Margo has made "Posts: 2869".
The little blue round world looking icon under the name and photo is a link to that person web site if they have one.
Hope I am making sense.