I am self taught with no background in Computer Science. Prior to my first job, I could barely use a computer.
In 1992 I failed my "Computer Driving Test" at University, which was
Using Windows 3.1:
Open a file using File Manager
Save it in a new location with a different name
1995-1996: Unix shell scripting to copy, create and delete audio files
1997: flow based programming of IVR systems such as C3 to answer phone calls
1998 - 1999: SCO Unix shell scripting; Programming in C; JavaScript/HTML web development (first Geocities page); IVR programming using Synamics; creating and managing a static corporate web site
1999: Esri Avenue and AML, more C (point-in-polygon analysis), CadCorp SIS, Visual Basic, ASP
2000: Visual Basic, ASP, JavaScript, AJAX
2000-2012: Esri ArcObjects (COM), Microsoft .Net, Java (JSP, IBM Portal server, Servlets), ASP.Net, C#
2012 - now: Java, PHP, python, Go, JavaScript, Swift, SwiftUI, Android