system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is Monsanto and why should I care?

Seriously I haven't read into any of this and would much rather have someone explain it to me rather than dig through articles.
gpt
Monsanto is a company takes seeds, changes their DNA, and gives the special new properties. They try to make new products that are better than what nature has provided by giving the seeds better yields, more nutrition, or resistances to things like pesticides and insects.

There are a few problems surrounding the company. Number one is that they patent the seeds they produce. Many people are upset about this because they are patenting a living thing. Lots of people say that nature has created life and therefore it should not be allowed to be patented. Other problems arise when seeds naturally spread onto farms that didn't buy them, thus violating the patent agreements. 

Number two is the loss of diversity. Nature has a way of creating genetic diversity among all the plants. If the plants have been genetically engineered, some people fear that there will be a loss in genetic diversity as people plant only the GMO crops and don't save the seeds, leading to genetic stagnation. Loss of diversity could pose problems if a virus evolves the ability to hurt this specific type of crop. Since all the crops would have the same genetic makeup, the virus could theoretically kill everything like in the Irish Potato Famine.

Lastly, some people claim GMOs cause adverse health effects. People claim that they cause cancer and all kinds of other diseases as well as contributing to declining bee populations. There have been reports that both prove and disprove these allegations but the problem is that this issue has been so heavily politicized and there is so much money on the table that the truth will be hard to find.

I think protesters today are angry about all these things. They don't want to eat GMOs, they don't want people to grow GMOs, and they don't want Monsanto to sell GMOs.