21. Procedural parameters as a programming language feature were introduced by ALGOL 60. 22. An S-algol program is a sequence of declarations and clauses. 23. S-algol attempts to improve this by providing less restrictive syntax. 24. Dynamically-valued constants originated as a language feature with ALGOL 68. 25. ALGOL introduced the use of block structure and lexical scope.26. Others advocated the opposite convention, including IBM for writing Algol programs. 27. The language itself was an extended version of Algol 60. 28. He was also involved in the design of Algol 68. 29. Another phenomenon observed in certain Algol binaries has been monotonic period increases. 30. The article about ALGOL is not quite explicit about this.
