A share of stock is ownership: you hold a slice of a real company. A CFD — contract for difference — is a bet on price movement without owning the underlying asset. They can track the same market, but they are not the same instrument.
The big difference is leverage. CFDs let you control a large position with a small deposit, which magnifies both gains and losses — you can lose more than you put in. Stocks, bought outright, can't fall below zero, and your downside is limited to what you invested.
Neither is 'better' — they suit different goals. Stocks fit long-term ownership and dividends; CFDs suit short-term, leveraged views for traders who understand margin. Know which one you're holding, and why, before you place the order.