Why do people consider all muslims bad people? Is that racism?

They don't and yes it's racist.

There are around 1.6 billion muslims in the world, It doesn't make sense to say all of them are bad or other things.

I won't say it's racist because Islam isn't a race ,but it's stupid.

It's unreasonable to consider all Muslims bad. Is it racism? No. Islam is not a race.

Not all people do that. You might get your sources checked and upgrade the range of your experience level.

Throughout history, there has been a lot of Muslim terrorist groups here and there who frighten the world. That does not mean all the Muslims are bad. Despite that, some people fail to understand and swallow this concept. Some because of their fear. Some because of their racist practices. Therefore, they create more tension and bring such stereotypes within the mind of people like you.i do not blame you. I have an Indian friend, her little brother was playing an online game, he met someone, a seven-ten years old kid. He said greetings and quickly added "and i am not a terrorist" this is so sad and i understand why.

Personally, i have Muslim friends around the world via internet. All awesome people. I do not embrace Islamic belief or culture. But i respect them and would never act inappropriate because of their lifestyle.

One of my Muslim friends from Lebanon came in U.S months ago via an educational program in Minnesota. (even she is in Muslim country, she is not really a Muslim tho) Everyone are okay with her , she having lots of fun and an American family hosting her. But in the middle. There are few classmates who think she is gonna kill them right away. It's sad but it exists! I know but there are only "some"

So with my examples and the answers here you can understand not everybody think like that. There are a few here and there. You must ignore those kind of unwise uneducated people.

There a fundamental problem with that question .. Because it is an innaccurate claim, it's hard to answer.

Problem stemming from your referrence to "people' .. Which is assumed to mean ALL people.  The truth is .. Not ALL people think all muslims are bad people because the truth of the matter is not ALL muslims are bad people.

You've chosen the wrong word. It's not racism, it's bigotry.

The fundamentalists of any religion are likely to act out their fantasies in anti-social ways. Sure, you've got Islamic groups liked ISIS and Al Qaeda, but you also have Christian groups like the Branch Davidians or the People's Temple of Jim Jones. Then, of course, you have evil little groups like the Westboro Baptists and various Christian militia groups.

For an outrageous Christian attitude to killing people try reading Chris Kyle's "American Sniper". Several times in it he boasted that he had killed many people but would stand, without judgment, before God because the people he had killed worshipped heathen gods and were just trying to kill Americans.

(I had no trouble with him killing the enemy; that's what soldiers do in wartime and he was good at it. It was his zeal about doing it as a Christian that alarmed me.)

You already know all people don't. Just you, you're the racist.

It comes with ignorance. Not necessarily by choice, but by their environment, surroundings, and upbringing.  Most of Islamphobia is concentrated in areas of the country where there are less than 50,000 people in tiny villages and townships where the racial make-up is 90% white. Their knowledge of things like Chinese food would be beef and broccoli or orange chicken, which isn't really Chinese food. Anyone wearing a Turban is a Muslim even though they might be Sikh. And  people tend to be afraid of what they don't know, especially those that choose to stay in their safe secluded environment outside of society where their only connection to the outside world is the TV or some poorly coded click bait websites.