How do you express "uppercase letters" and "lowercase letters" in English?

The English expressions of "capital letters" and "lower case letters" are as follows:

1. Capital letters: capital letter, majuscule. Example:

(1) 'Ecu '?was?printed?in?lower?case?rather?than?capital?letters.?ecu is printed in lowercase letters instead of capital letters.

(2)In?this?writing,? some?punctuation?and?capital?letters?have?been?left?out. In this writing, some punctuation and capital letters are no longer there.

(3) Capital?A;?great?A. ;?many?medieval?manuscripts?are?in?majuscule?script. Capital A; Capital A; Many medieval manuscripts are written in capital letters

2. Lowercase letters: lowercase Example: < /p>

（1）Lowercase?letters?in?the?text?are?left?unchanged.The lowercase letters in the text remain unchanged

(2)They?simply?convert? the?string?to?all?uppercase?or?all?lowercase?letters,?respectively.?They just convert the strings into uppercase letters or lowercase letters respectively.

(3) Variable'underscore. ?and?the?name?of?variable?starting?with?a?lowercase?letter.

Extended information:

Uppercase letters. Or uppercase is one of the writing forms of many pinyin letters, such as A, B, C, etc. The height and width of uppercase and lowercase fonts are obviously different, but in some languages, they are not case-sensitive, such as Latin. In the early days of the invention of letters, there was only one font, namely uppercase letters

Reference: Baidu Encyclopedia_Uppercase Letters?Baidu Encyclopedia_Lowercase Letters