It must also be noted that Bitcoin Gold is different from another fork that is scheduled for November: Segwit2x. The November fork is aimed at increasing the capacity of the network where as the Bitcoin Gold split is looking to cut more people in on the mining pie.
A change in the hash
It used to be that mining was totally open to anyone who felt like firing up the software on their home computer. However, over time, Bitcoin mining became relegated to expensive custom miners operated in giant factories to achieve economies of scale.
Bitcoin Gold is changing their proof of work algorithm to Equihash, something fans of Zcash will be familiar with. It's a "memory-hard" algorithm, which means common home computer hardware like GPUs will be able to profitably mine Bitcoin Gold for the foreseeable future.
