I'm still not sure how shorting is even legal or what useful purpose it serves in the stock market. Wasn't the whole idea that people can invest arbitrary amou

I'm still not sure how shorting is even legal or what useful purpose it serves in the stock market. Wasn't the whole idea that people can invest arbitrary amounts to companies by buying their stock, making investing more efficient? How the hell did we get from that to people using it for outright gambling with shorting ??