Besides the integrated circuit and family concept, several other noteworthy developments characterized the third generation. Perhaps the most important of these were the operating system, continued improvements in programming languages, the minicomputer, and work processing.
1. Operating Systems :
An operating system is a set of control programs that supervises the work of the computer systems. Programs were entered one by one and monitored individually by the computer operator.
Also, automatic communication between the CPU and devices such as the printer was not yet possible; these elements had to be coordinated manually. With operating systems, however, these tasks could be performed automatically under program control.
Also, computers in the first and second generations were serial processors; that is, they would do all their work in a one-program-at-a-time fashion. For example, job 1 would be started and completed, and job 2 would be processed, and so forth.
Many modern operating systems enable computer systems to speed up processing by working on several programs concurrently.
2. Improvements in Software :
The development of new high-level programming languages flourished in the third generation. Each new language was created in response to the needs of an important market of users.
BASIC (Beginners All-purpose Symbolic Instruction Code), for example, was developed to address the need for a programming language that was easy to learn and use. It is still one of the most popular languages for microcomputer systems.
The development of RPG (Report Program Generator) in the mid-1960s signaled a new trend in programming languages. With RPG, a use or programmer merely describes to the computer system what a report is to look like, not how to produce it.
Once given the input/output formats and formulas for calculations, the computer system automatically generates its own computer program to produce the report. These report-generator languages have proven to be incredibly time saving, and companies use them extensively.
An additional boost to the quality of software came in 1969, when IBM which was rapidly becoming a virtual monopoly- was forced through government pressures to “unbundle” pricing on software and hardware.
Roughly speaking, this meant that organizations would be billed separately for hardware and software. Users of IBM equipment were no longer locked into acquiring their programs from IBM.
Almost immediately, dozens of companies went into the business of designing better and cheaper software for IBM machines, which dominated the marketplace at that time. Many succeeded, and the software industry soon mushroomed.
3. The Rise of the Minicomputer :
In the mid-1960s, the first successful minicomputer was built. The mini- a scaled-down version of larger computers of the day- was largely the brainchild of an electrical engineer named Kenneth Olsen.
Olsen saw early on the need for a small, rugged, inexpensive computer, one that didn’t need to be housed in a computing center and tended to by a staff of trained operators.
Together with his brother and another engineer, Olsen founded Digital Equipment Corporation (DEC) in an old brick wool mill in Maynard, Massachusetts. Their first successful mini, a refrigerator-sized computer called the PDP-8, cost about $18,000. It became widely used in both small and large companies.
Following DEC’S success, other companies soon started to manufacture minis. Data General, founded by four engineers (three of whom had worked for DEC), was another early entrant into the minicomputer market.
In 1969 Data General introduced its Nova minicomputer, which sold for a mere $8,000. The race for inexpensive computers was on.
4. Word Processing :
Word processing refers to using computer technology to assist in the typing of documents. IBM coined the term in 1964, when it first marketed the magnetic tape selectric typewriter (MT/ST).
This machine enabled secretaries to store “canned” portions of documents on a tape unit connected to the typewriter and to interweave fresh text with prepared materials. Today, of course, the tape units are gone and word processing has been enhanced by disk units, display screens, and large electronic memories.
Word processing initiated the widespread use of computers in office settings, a phenomenon that many people refer to today as office automation (OA).
Later, in the 1970s and 1980s, innovations such as desktop microcomputer systems, electronic mail, desktop publishing systems, facsimile (fax) machines-, and intelligent copiers would further fuel the rise of OA in organizations.