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The type str represents text. Single and double quotes both make strings; triple quotes allow physical newlines. Escapes include \n, \r, \t, escaped quotes, \\, \0 for an embedded NUL, and \u{H...} for any character by its hexadecimal code point, such as "e\u{301}" for an e followed by a combining accent. See escapes.

def main() -> Result[(), IoError]:
    name = 'Plenty'
    print(name)?
    print(contains(name, "lent"))?
    print(len("hé"))?
    print("hé".byte_len())?
    Ok(())

Plenty
True
2
3

print displays text without quotes. contains(text, part) tests for a substring. len counts Unicode scalar values, so the accented character above counts once; this is not a count of visible grapheme clusters. byte_len() gives the size of the UTF-8 encoding instead, which is what a file, a buffer, or a size limit measures.

Strings are immutable. A mut binding allows replacing a string, rather than editing its bytes.

Compare strings in Unicode scalar order, inspect ASCII characters, or convert a single character to its code point:

def main() -> Result[(), AllocError | IoError | ParseError]:
    print("apple" < "pear")?
    print("abc".isalpha())?
    print("123".isdigit())?
    print(ord("é")?)?
    print(chr(233)?)?
    print("Hello".lower()?)?
    print("Straße".upper()?)?
    print("  one\t two\n".split()?)?
    Ok(())

True
True
True
233
é
hello
STRASSE
["one", "two"]

ord requires exactly one Unicode scalar; chr takes a u32 code point and rejects surrogates and values outside Unicode. Both return Result and allocate nothing. Case conversion and splitting return fallible, independently owned results. The ASCII predicates return false for empty or non-ASCII text.