Hi @PhoebeWai, there is no agreement of what constitutes hate speech precisely at an international level, but many, many democracies have laws defining it & prohibiting it in varying ways. These laws, in many cases, have also been written with a view to balancing the rights of freedom of expression as well - it can be a complicated, but critical balancing act.
Here are 3 examples to give you a better idea and even though they are different they cover the ground well of what hate speech is & what it can incite in the way of discrimination, harm or violence.
"The European Court of Human Rights, in a definition adopted by the Council of Europe’s
Committee of Ministers, considers ‘hate speech’ as: “all forms of expression which spread,
incite, promote or justify racial hatred, xenophobia, anti-Semitism or other forms of hatred
based on intolerance, including intolerance expressed by aggressive nationalism and
ethnocentrism, discrimination and hostility towards minorities, migrants and people of
immigrant origin.”9
– YouTube, in its community guidelines, describes ‘hate speech’ as: “content that promotes
violence or hatred against individuals or groups based on certain attributes, such as: race
or ethnic origin, religion, disability, gender, age, veteran status, or sexual orientation/
gender identity.”10
– The Broadcasting Complaints Commission of South Africa considers ‘hate speech’ to be
“material which, judged within context sanctions, promotes or glamorizes violence based
on race, national or ethnic origin, colour, religion, gender, sexual orientation, age, or
mental or physical disability” or “propaganda for war; incitement of imminent violence; or
advocacy of hatred that is based on race, ethnicity, gender or religion, and that constitutes
incitement to cause harm.” 12"
Source: https://www.article19.org/data/files/medialibrary/38231/Hate_speech_report-ID-files--final.pdf