What is greenwashing, the practice major companies are accused of engaging in?

What does 'greenwashing' mean and why is it a problem? Why do big brands like Coca Cola engage in it? Greenwashing serves as a smokescreen which hides the continued exploitation of the planet and allows those responsible to get away with it. "The number of products labelled as sustainable or green has increased exponentially in recent years, with many household brands guilty of greenwashing. Yet, as businesses claim progress towards sustainability, emissions continue to rise, extraction increases, and overproduction spirals," says Changing Markets Foundation (CMF)