After we listen to songs on a music app, we are surprised to see recommended（推荐的）songs. When we open shopping websites, we can easily see things that we might want to buy.
This is based on data（数据）. Data is not only about numbers but also information from every side of our lives: our shopping habits and interests... All of this is called "big data."
In December, President Xi Jinping called for China to accelerate its big data plan to serve the development better and improve people's lives. He also asked for greater use of big data in fields like education, social safety and transportation（交通）.
Big data have been used more often in China in the past few years. Its role in tourism is just one example.
The data that travelers share online give the tourism industry a lot of information about the country's tourist places. After studying the data, different tourist places can create their own online instructions. The instructions show travelers, reviews and services needed to be improved.
Big data is growing quickly, With a growth of 30% every year, sales of big data services and products in China will reach 1 trillion（万亿）yuan yearly by 2020, China News Service reported.
