Hi Nessie
At the bottom of your avatar there are three symbols, the green blob to say you are online, the funny one next to it is the rep symbol. If you see a post that offers good support or that you like you can press the button and rep somebody, this will increase their rep points. If someone reps you, you will be able to see what post they gave it for but not who gave it to you.
Hope this helps.
Georgie
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