Question about Lesson 7. Between

I was confused between the two examples given in this exercise, the first one was <SELECT * FROM movies
WHERE name BETWEEN ‘A’ AND ‘J’;> where it only returned values from A to I not including ‘J’. But in ht second example <SELECT * FROM movies WHERE year BETWEEN 1990 AND 2000;>it returned values from 1990 to 2000 including ‘2000’. I don’t understand why it did this thing in 1st example it did not include the value after AND which was 'J’and in the 2nd example it included the value after AND which was ‘2000’.

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= Question About Like-II Lesson