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Why do share prices move up and down?
Can you please explain in details behind who calculates that share should move up or down EVERY SECOND? How is this even possible?
Is this done by Computer System? How can a computer in real-time calculate the mentioned factors such as the company's financial result, overall economy situations, sector performance, government rules & regulations, major political & natural events, future of the company, upcoming products & services, company management changes, stock market frauds, etc?

How does the computer even calculate this? Is the Stock market controlled and manipulated by UNKNOWN people?