The whole industry is moving into new paradigm after PC era. According Gartner the subjected technologies are among top ten.
Amazon , Google, Microsoft and other firms are to spending lot money in this area. Lot of research and development is progressing in this areas.
And these emerging technology are future of the industry.Lot of firms are taken/taking this road.
Bigdata talks about of volume of data . And also complex real-time or non real-time. There various means you store, analyze and process. Cloud is one such method to do that.
Cloud is more on service models. Also it is going to deal with where it is stored, and how firms can access.
Data Analytic is about data analysis. This data can be used take business decisions and sections.
Hope you got the picture. Please feel free to comment and suggest.