Difference between Ethereum and Ethereum Classic 

Now, down to differentiating the both.

Technically speaking, both chains are similar and only differ in being updated. 

The original Ethereum, now known as Ethereum Classic (ETC), is completely separated from all updates of Ethereum(ETH). 

This means that Ethereum Classic is completely programmed with the original model. 

Also, it contains no revised developments that Ethereum has made so far, including the Ethereum 2.0 version.  

This also means that Ethereum Classic is a ledger with the record of the infamous hack, whereas Ethereum contains no such record.