The Python Tutorial Python Programming Language

Python is a programming language that lets you work more quickly and integrate your systems more effectively. You can learn to use Python and see almost immediate gains in productivity and lower maintenance costs.

You've never programmed in Python before. Should you start now?

Yes. This is as sure a bet as you're going to get in the technology horse races: The benefits of the Python programming language are so many, and its costs so low, that you're almost sure to come out ahead.

Python's strength is its universality. Once you learn it, you'll find you can use it for nearly all the programming you do. Press coverage might have led you to think that it's "just a scripting language for the Web," or only used by academics. As good as Python is in those roles, you'll see below how it also does much more. Among other things, Python is: a starter language, scalable to large professional programs, graphically savvy, and it even does windows!

A Starter Language

Are you a newcomer to programming? Python is an ideal first language. It originated in a 1980s project to design a language for beginners. Its maintainers have always shown a willingness to "do things right." The Python world understands that phrase to mean they make the language logical, simple, and inviting, even at the occasional expense of conflict with industry traditions.

Python insiders don't just talk about "outreach" to non-programmers. The Python community supports an active "Programming for Everybody" Special Interest Group. Python founder Guido van Rossum's current principal project, funded by the Department of Defense's Advanced Research Project Agency, is on the same topic.

The Python features newcomers most applaud include:

• Its availability: There's no charge for using Python, and essentially identical versions are available for Windows, MacOS, Linux, BeOS, other Unixes, and many other operating systems.
• Its interactivity: Once installed, a Python user can immediately interpret his work. Type a line of source code, and Python processes it as soon as you hit "Enter." That short feedback loop is especially important for beginning programmers.
• Its simplicity: Guess what
  

    current = 2000
    start =   1990
    elapsed = current - start
    print elapsed

  does. You're right -- and you've just read your first Python program. Python minimizes unpleasant surprises and "trickiness."
• Its power: Python developers typically report they are able to develop applications in a half to a tenth the amount of time it takes them to do the same work in such languages as C. While "power" and "expressivity" seem to have unquantifiably subjective components, experts generally agree that Python has as much or more of these good things as other languages.

Scalability

Scalability is nerdspeak for "travels well and doesn't let me down." While Python is great for beginners, it also fills the needs of expert users. Other languages popular in educational settings have been scorned by working developers as too slow, incapable of connecting to existing resources, or too inflexible. Few complain about Python in these regards. Python stretches all the way from beginners' one-liners to some of the largest and most demanding computer programs. Python is in use, for example, as part of very complex supercomputer analyses of metal fractures.

We need to be careful about several key concepts in understanding Python's capabilities "on the high end." The metal structure application just mentioned uses Python in crucial ways; in fact, insiders have said that the project simply wouldn't have succeeded without Python. However, most large Python-coded programs, including this one, have a majority of their source written in such other languages as FORTRAN, Java, C, and C++.

Each of these other languages is superior in certain aspects: speed, scientific calculation, graphics manipulation. Each also has characteristic weaknesses. The search for the one true language to use for complex projects is a mistake. The more rational approach is to find the right mix of languages and "glue" them together with Python. You will end up with more efficient, error-free, and maintainable code by using Python to combine the best of each of these.

Because it plays nicely with other languages, Python doesn't create dead-ends. While this idea is hard to make precise, experienced programmers recognize it. Programs begun in Python have good lives; they don't hit limits in speed or algorithmic sophistication which cause them to stagnate. They grow with your needs and your abilities. I almost always feel safe in choosing Python for a project. Even when information turns up during the life of the project that was unknown at the beginning, I have confidence that Python's flexibility will accommodate new needs and constraints.

For technical reasons, also, Python's "object-oriented" syntax has proven to be excellent for teamwork. Experience has shown that engineers working in different areas, and even the same programmers returning to old programs, read unfamiliar Python source code comfortably. This is Python's greatest strength in my own work. As a highly-expressive, object-oriented, well-structured, interoperable language, it promotes the success of large complex projects in a way no other language does