The history of software development incudes numerous textual and graphical ways to represent software structures and the mechanisms for executing high-level instructions. The proliferation of programming languages is a visible outcome of that effort, with many popular languages having a strong association with their creator(s). In this paper, we present a historically focused overview of many different types of software representations, primarily programming languages, but also graphical notations that can generate code in a programming language or be directly executed with associated tools. The paper then describes some of the characteristics that differentiate them from one another, and concludes with a review of guidelines for designing programming languages and notations.

Anthony I. (Tony) Wasserman has divided his career between academia and industry. He is Principal of Software Methods and Tools, which provides consulting services on software development processes, as well as serving as an Advisor to software-centric businesses and their executives. From 2005-2023, he was a Professor in the Software Management program at Carnegie Mellon University - Silicon Valley, teaching courses on software product definition, software product strategy, open source software, and more.

Earlier, Tony was founder and CEO of Interactive Development Environments (IDE), creator of the innovative Software through Pictures development platform, one of the first 100 dot-coms. Tony then led an early mobile app development team at Bluestone Software (acquired by HP), and held executive positions (VP Engineering, VP Product Development) at several startups. Early in his career, Tony was Professor of Medical Information Science at the University of California - San Francisco, and a Lecturer at the University of California, Berkeley, leaving to start IDE.

His professional service includes roles in organizing many technical conferences, including Program Chair for the Software Product Management Summit, sponsored by the International Software Product Management Association. He has also served on program committees for ICSE, SEET, the International Conference on Open Source Systems, and the Linux Foundation’s Open Source Summit. He served two terms (2010-16) as a Director of the Open Source Initiative, and was a co-founder and first elected Chair of ACM’s SIG on Software Engineering (SIGSOFT). He has led international working groups on Information Systems Engineering and Open Source Systems.

Tony has published nearly 100 reviewed papers, edited 13 books, and was Editor-in-Chief of ACM Computing Surveys. He currently serves as an Advisor at UC Berkeley’s SkyDeck accelerator. Tony earned a Ph.D. in computer sciences from the University of Wisconsin - Madison and a B.A. in mathematics and physics from the University of California, Berkeley. He has been honored as a Fellow of ACM, the IEEE, the International Federation for Information Processing (IFIP), and the International Software Product Management Association (ISPMA).

Tony has served as a Visiting Professor at the Vrije Universiteit (Amsterdam), the Université de Genève, and the National University of Singapore. He has visited more than 75 countries. He has had the good fortune to travel to more than 75 countries, and posts many of his photos on Flickr.