“Hello, world” programs vary in complexity between different languages. In some languages, particularly scripting languages, the “Hello, world” program can be written as one statement, while in others (more so many low-level languages) many more statements can be required. For example, in Python, to print the string Hello, world followed by a newline, one only needs to write print("Hello, world"). In contrast, the equivalent code in C++ requires the import of the C++ standard library, the declaration of an entry point (main function), and a call to print a line of text to the standard output stream.
The phrase “Hello, world” has seen various deviations in casing and punctuation, such as the presence or absence of the comma or exclamation mark. Some devices limit the format to specific variations, such as all-capitalized versions on systems that support only capital letters, while some esoteric programming languages may have to print a slightly modified string. Other human languages have been used as the output; for example, a tutorial for the Go language emitted both English and Chinese or Japanese characters, demonstrating the language’s built-in Unicode support. Another notable example is the Rust language, whose package management system creates a program that prints “Hello, world!” as the default for new projects.
with a moving strip of light-emitting diodes (LEDs)
Some languages change the function of the “Hello, world” program while maintaining the spirit of demonstrating a simple example. Functional programming languages, such as Lisp, ML, and Haskell, tend to substitute a factorial program for “Hello, world”, as functional programming emphasizes recursive techniques, whereas the original examples emphasize I/O, which violates the spirit of pure functional programming by producing side effects. Languages otherwise able to print “Hello, world” (assembly language, C, VHDL) may also be used in embedded systems, where text output is either difficult (requiring added components or communication with another computer) or nonexistent. For devices such as microcontrollers, field-programmable gate arrays, and complex programmable logic devices (CPLDs), “Hello, world” may thus be substituted with a blinking light-emitting diode (LED), which demonstrates timing and interaction between components.
The Debian and Ubuntu Linux distributions provide the “Hello, world” program through their software package manager systems, which can be invoked with the command hello. It serves as a sanity check and a simple example of installing a software package. For developers, it provides an example of creating a .deb package, either traditionally or using debhelper, and the version of hello used, GNU Hello, serves as an example of writing a GNU program.
Variations of the “Hello, world” program that produce a graphical output (as opposed to text output) have also been shown. Sun demonstrated a “Hello, world” program in Java based on scalable vector graphics. Mark Guzdial and Elliot Soloway have suggested that the “hello, world” test message may be outdated now that graphics and sound can be manipulated as easily as text.
In computer graphics, rendering a triangle—the “Hello Triangle”—is sometimes used as an introductory example for graphics libraries.ld go to your dashboard to delete this page and create new pages for your content. Have fun!