The character of programming languages

Many languages use C-style blocks denoted with braces (the characters '{' and '}').

The BCPL programming language was the first language to use braces as part of its syntax. Earlier languages (notably COBOL, FORTRAN, algol, and LISP) did not use the brace characters.

Earlier languages did not use brace characters because the characters did not exist, at least not as defined characters. There was little in the way of standards for character sets, with each vendor (and sometimes each system) using its own character set. For a language to run on multiple computers, one had to limit the characters used in the language to those available on all planned platforms. Thus, FORTRAN uses uppercase letters and parentheses but not square brackets.

With the introduction of the ASCII and EBCDIC character sets, things changed. A standard character set (well, two standards) let one assume the existence of all of the defined characters.

First published in 1963, the character sets predate the effort to build BCPL in 1966. Thus, when BCPL was designed, the brace characters were present and ready to be used. They also have the virtue of not being used for anything before.

Our character sets define, to some extent, the syntax of our languages.