General & Frequently Asked Questions, page-4

But just for others.

"An option is a contract between two parties giving the taker (buyer) the right, but not the obligation, to buy or sell a security at a predetermined price on or before a predetermined date. To acquire this right the taker pays a premium to the writer (seller) of the contract."

Basically its a share thats not been paid for yet. In the example of XPEOB if you buy an option in XPE you can then trade them just like normal shares. Buy and sell them normally using that code XPEOB. If you would like to convert them into standard shares, you just need to contact the company XPED directly to arrange to do so, these particular options will cost you 1.5c each to convert. You can convert or sell them any time before the expiry date which for XPEOB is the 21st of July 2016.