です makes what you're saying polite and adds an amount of certainty. It's somewhat equivalent to 'it is' in English.
To contrast, the difference in English would be something like:
Alice is a student. - アリスは学生。 It is Alice who is the student. - アリスは学生です。
In casual talk, there is no difference.
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です makes what you're saying
です makes what you're saying polite and adds an amount of certainty. It's somewhat equivalent to 'it is' in English.
To contrast, the difference in English would be something like:
Alice is a student. - アリスは学生。
It is Alice who is the student. - アリスは学生です。
In casual talk, there is no difference.