The big data have various challenges like heterogeneity, scale, timeliness, complexity, privacy problem. This paper addresses these challenges. As Data is being collected at huge amount of scale, in a broad range of application areas. Previously decisions were based on guesswork, or on painstakingly constructed models of reality but now they made based on the data itself. Nowadays Big Data analysis drives every aspect of our modern the world, including mobile services, retail, manufacturing, financial services, life sciences, and physical sciences. To take full advantage of visual analytics, organizations will need to address various challenges related to visualization. This paper addressing is done about various big data analytics opportunities, challenges and tools.