This section will cover computer programming, including its history and the progression of computer-programming languages.

Computer Programming

A computer program is a set of step-by-step instructions that tell a computer exactly what to do. People who write computer programs are called programmers.

When the step-by-step instructions are followed, the results will be those anticipated by the programmer. The computer program will include decision points and actions to be taken depending on the decision made.

Computer Programs

Places Where Computer Programs Are Used

There are computer programs working behind the scenes in many places. Grocery stores use computer programs to scan the labels on

grocery items. Hospitals use computer programs to keep patient records and

scan identification bracelets. Colleges use computer programs to register students for classes

and calculate grades. Gas stations use computer programs to dispense gas and accept

payment. Banks use computer programs to dispense cash and track

account balances.

The content of a computer program is called code.

The sample code on the right is written in Python. It first defines fruits, and then it instructs the computer to print the statements with the appropriate fruits.

Example of a Computer Program

Computer Programming

Computer programming is the process of writing the step-by-step instructions a computer can understand.

The first step in computer programming is defining the problem.

The next step is creating a logic problem that can be solved using a computer program.

Writing the actual program is the last step in the process.

Computers read binary machine language made up of 0s and 1s. Because it is difficult for programmers to create a program in machine language, high-level programming languages have been developed.

A compiler or interpreter is then used to translate the high-level programming language into the machine language that the computer can understand.

Computer-Programming LanguagesLike all forms of language, computer-programming languages enable the communication of information. Programming languages allow programmers to communicate instructions to the computer.

Just as there are different languages like English, Spanish, and French, there are different programming languages. These programming languages have their own syntax, which are rules for how the language is used. In the same way that French and Spanish use different words to mean the same thing, different programming languages use different commands to achieve the same result.

Panel switches were used by hand to program computers in the 1940s to enter instructions and data. It was important that the programmers knew the instruction set for each processor.

As computers became more advanced, computer programs began to handle some of the entering of the instructions and data.

Programmers would handwrite the directions in assembly language programs. Then the Assembly language, a low-level programming language, would translate the instructions into binary machine language for the computer to understand the directions.

1940s: Programming Languages

1950s: Programming Languages

The first high-level programming languages were created in the 1950s. Examples include the following:

FORTRAN was the first high-level programming language and used the first compiler. FORTRAN is an acronym for FORmula TRANslation. It remains a top language in scientific programming.

COBOL was one of the earliest high-level programming languages designed for business applications. COBOL is an acronym for Common Business-Oriented Language.

LISP was developed and used for research in artificial intelligence.

During the 1960s, two important programming languages were developed: C and BASIC.

First the B and then the C computer-programming languages were developed in the 1960s at Bell Laboratories. Later in 1973, Unix was written in C programming language. Can you believe this simple operating system became the inspiration for Linux and Apple OS?

In 1964, the BASIC programming language was developed at Dartmouth College. BASIC is an acronym for Beginner’s All-purpose Symbolic Instruction Code. This language was designed to make it easy for students to write programs at shared terminals while learning programming at the college.

1960s: Programming Languages

1970s: Programming LanguagesDuring the 1970s, Microsoft began to release computer-programming software, and a programming language was developed for use in teaching programming.

Pascal programming language was first defined in 1971, with revisions released in 1973. It was designed to teach programming to college students. Until the 1990s, it was considered the best language for teaching programming.

In 1975, Microsoft announced the release of Altair BASIC, the first programming language for personal computers.

1980s: Programming LanguagesMany new programming languages were developed and introduced in the 1980s.

Ada was published in 1980 as the result of a comprehensive development project by the US Department of Defense (DoD) to create a standardized programming language to replace the 450 programming languages used across the DoD and in the Army, Navy, and Air Force.

Microsoft developed versions of BASIC, FORTRAN, COBOL, and Pascal for IBM for its personal computer in 1980.

C++ programming language was released by Bjarne Stroustrup in 1985.

Borland’s Turbo Pascal programming language was released. dBASE programming language and database formulae was

developed. Perl programming language was created in 1986. Perl is an

acronym for Practical Extraction and Report Language. Microsoft released Visual BASIC in 1987.

Introduced in the 1960s, object-oriented programming (OOP) grew in influence in the 1980s. With object-oriented programming:

a program is divided into parts known as objects.

objects can contain data. objects can contain programs that

perform a specific function.

The “objects” in OOP were important because they allowed programmers to handle increasingly complex programs and collaborate more effectively.

Importance of Object-Oriented Programming

Web-based programming, also known as browser-based programming, is a significant innovation of the 1990s through present time.

Web-based programming enables your web browser to access a server maintained by a large company or other organization. For example, an online merchant uses a server that you can access using your web browser so you can buy products from their website.

Java programming language was developed at Sun Microsystems and released in 1995. Sun Microsystems has since merged with Oracle, which oversees the continued development of the language

1990s through Present time: Programming Innovation