What does the 'ECO' button do in a Ford Puma?

I noticed there is an 'ECO' button in my new Ford Puma but I'm not sure what it does. Can someone explain its function and if it's worth using?

The 'ECO' button adjusts the car's performance and reduces fuel consumption. It's helpful for city driving and can save you money in the long run.

I always turn on the 'ECO' button as it helps with smooth acceleration and better overall efficiency. It's definitely worth using, especially for longer drives.

I never use the 'ECO' button as I prefer a more sporty driving experience. It's up to personal preference, but keep in mind that it may impact your overall fuel consumption.