So, you know how schools have grades, right? First grade, second grade, third grade, and so on. Well, different countries have different ways of organizing their schools and their grades. This can make it really hard to compare the education systems of different countries or understand what someone's education means if they're from a different country.
To solve this problem, people came up with something called the International Standard Classification of Education, or ISCED for short. This is basically a system that tries to make education levels across different countries more comparable.
It works like this: there are different levels of education, and each level has its own code. For example, primary education (which is like elementary school) is code 1, lower secondary education (which is like middle school) is code 2, and so on. Each level also has specific criteria that need to be met for it to count as that level of education.
So, if someone tells you that they completed ISCED level 3, you know that they've completed upper secondary education (which is like high school) in a country that uses the ISCED system. This makes it easier to compare education levels across different countries and understand what someone's education means.