Software: OS, applications, programming

Software: this is what makes the system functional. There are two types: system and application.

System software – runs the hardware. In other words, this forms the background which gets everything up and running - and all the hardware speaking to each other.

• Also known as the operating system (OS)
• Includes DOS, Windows (3.x, 95, 98, ME, XP, Vista, 7, 10), OS X (apple), UNIX etc.

Application software – runs on top of the system, does something – i.e. word processing, spreadsheets, GIS, etc…

Programming languages

Their purpose is to write code which will do something. This could be an extension to an operating system, a new application, or a modification to either.

• remember, computers understand binary ONLY. Thus, early programs were created using Ones and Zeros only.
• many different types of languages: https://www.computerhope.com/jargon/num/1gl.htm
  • first generation - machine code (1,0) (binary)
  • second generation - assembly language. Think of this as machine code with built-in shortcuts. A bit easier to use, but not what you would call friendly. However, it is still used occasionally - mostly because it is VERY efficient.
  • third generation - standard programminglanguages including BASIC, C, C++, Java, Visual Basic, etc...
  • 4th generation - higher level stuff - macro programming, SQL, etc. In other words, this is a means of customising software using built-in tools.
  • 5th generation - natural language type stuff... Talk to your computer and it does stuff. Still pretty much in the realm of science fiction.

  What about GIS. What software do they use?

• If you want to customize ArcGIS, the current language is Python. Before this, it was Visual Basic. Before that, Avenue (a custom programming language), and before that, AML (macro level programming in workstation ArcGIS).
• Beyond this, you would look to Visual Basic for user interface coding and Java for web-type work.
• If you need to do some serious number crunching, grab C++ (or other varieties of C).

Often, more than one program will be used. For example, I have seen people write serious number crunching code in C++, then write a VB (or python) interface that calls the C++ code.