For a Marketer,  before the arrival of digital era the marketing wasn't as complex as its now days are, the sheer reason is the limited numbers of channels and mediums to reach the consumers. However with the evolution of internet & cloud which we favorably calls - digital age, the marketing is more exhaustive and intriguing because the channels of marketing are becoming almost limitless.
SMAC - Is the new wave of technology targeted for digital marketers. Given stack of technologies encompass the combined use of social, mobile, analytic & cloud computing. I believe the marketers who conceptualize the use of these 4 technologies together as a one stack can drive higher Customer Engagement, Greater Innovation & Exponential Growth in the opportunities unlike in previous waves personal compute & internet revolutions.
- Online Presence - Websites, SEO, SEM, Videos, Mobile Apps
 - Social Medea tools - Facebook, Twitter, Instagram, Pinterest, FourSquare, Linkedin
 - Printmedia, newspaper, TV News, RSS..
 
SMAC - Is the new wave of technology targeted for digital marketers. Given stack of technologies encompass the combined use of social, mobile, analytic & cloud computing. I believe the marketers who conceptualize the use of these 4 technologies together as a one stack can drive higher Customer Engagement, Greater Innovation & Exponential Growth in the opportunities unlike in previous waves personal compute & internet revolutions.
These should be also viewed as a set of
complementary technologies, where :
Social - Context Comes before the conversation and transpires into  “Engagement”
Mobile - Brings the “Always On” effect with
multiple devices; channels
Analytics  Drives “Actionable Insights”
And Last but not least Cloud makes
it “Real Time” & “Flexible” 
As a marketer you always think 
through your marketing strategy and all this through with a limited 
budgets. Technology is the back pockets tools for a marketer of today's 
times. He banks on it heavily, and effective use of technologies can 
take marketing efforts to different levels. SMAC will be a great tool 
set for a marketer to drive his marketing campaign effectively.