Two terms that are often used interchangeably, yet have differing ramifications are digital strategy and digital transformation. The scope of the former may be quite narrow. It usually serves any particular stakeholder group within the business such as customers, partners, suppliers or employees. It involves the usage of digital marketing for B2C players, marketing automation, use of digital tools or CRM or extraction of business intelligence using social media monitoring. Digital transformation involves the entire gamut of processes where digital technologies impact from scratch. This includes artificial intelligence, predictive analytics and cloud computing. It also involves sensors and robotics tools.

Source:- http://www.innovationexcellence.com/blog/2016/02/17/digital-transformation-versus-digital-strategy/