confused about words

I'm still new to this trying to figure out whats all this fancy words like threads does this mean adds and how do I post my car If anyone can help please respond

 

hi, the gonz. a thread is where someone starts a topic and members post replies to the topic. im pretty new myself and found that you just got to look around and read heaps. yourll pick it up quickly and every question you have, someone has asked it before so the answers are here someplace. enjoy!

 

Yea, now this thread is three posts long.