In simple terms, white hat SEO is the ethical way of optimizing your website. To make it more specific, white hat SEO fulfills these 3 criteria internet optimizer. 1. Follows Googles guidelines
Google has laid out a set of guidelines to follow for optimizing a website. These guidelines can be summed up in simply three words "Don't be deceptive". So if you are not corrupting Googles algorithms or manipulating rankings that means your using white hat approach.