The goal of early calculating machines was to simplify difficult sums. But with the help of new technology, electronic chips replaced tubes and a revolution of artificial intelligence has arisen. From then on, the appearance of computers totally changed our lives. They can not only download information from the wet when connected by the network or mobile phone signals, but also solve different types of logical problems. With operators as their coaches, they can even control rockets explore the moon and instruct androids of human race’s characters to mop floors and watch over your naughty niece. Anyhow, computers are so helpful that they do bring happiness.

However, computers are easily attacked by viruses. This reality has become a hard-to-dealwith- problem. As a result, computers are dangerous in a way. So, personally, I worry about their universal applications in some fields, such as finance.