International Computers Ltd: Meaning (information, definition, explanation, facts)

International Computers Ltd (ICL) was a large british computer hardware company that was rebranded as the European services arm of Fujitsu in 2002. Significant contracts include Post Office Ltd, Inland Revenue and NHS.

This article will expanded over the next few weeks and your contributions that would be greatly appreciated. (My old grey cells are failing).

History

International Computers Ltd was formed around 1974 from a merger of International Computers and Tabulators (ICT), English Electric, and Elliot. This was an initiative under Tony Benn, the UK Minister for Technology , to create a British computer industry that could compete with major world manufacturers like IBM.

ICT had emerged in the UK with the punch card era, equipment that would process data encoded on punched cards - 40 column cards in the case of ICT - (compared to the 64 or 80 column cards used by IBM and its predecessors).

Initially the data was punched into punched cards and then veried (by a second operator) prior to processing, hence the job title of Punch Card Operator.

The resulting packs of punched cards were then processed, initially to agree the batch of data with pre-prepared control totals, and then accepted into the operational systems.

Other equipment such as sorters, collators, and tabulators were used to prepare and process the batch(s) of punched cards (hence the term Batch Processing).

The tabulator/accumulators could tabulate (or print) the information from the cards, and although mechanical with typically 120 or 132 hammers would print a line of output (line printing) for each card read. They were also capable of accumulating totals that could be printed as necessary.

Typical operations were for census work, and business tasks such as payroll, invoiving and stock control.

Tabulator connection and punch boxes - The operations were programmed using hard-wired connection boxes that controlled the operations undertaken, the coloums to be totalled, and the fields that identified the type of records, and the needs for sub-totalling and totalling. A different connection box would be prepared for each task and kept for re-use on the particular task.

An additional unit that could be coupled to the rear of the tabulator was a summary punch that would prepare summary cards for each customer, stock item, etc. with totals. These were typically used so that the accumulative results could be output fopr use in the subsequent period.

These tabulators, by modern computer standards were very large, and occupied an area 6 feet by 4 feet and stood 5 feet tall.

Early Computers - A subsequent additition was a computer, or calculating device. I think this was the 553 or 555, that enabled cards to be read in , calculations made, and a new card punched out with the added information.

I can recall that these devices were expensive for the time, and we bought a days time from a user that had one. We arrived with a car full of metal trays containing the punched cards and returned with an extra set of updated cards. By the stanadards of the time these were very fast, but with todays computers similar calculations would be performed in minutes.

The devices of this era, which had substantial mechanical parts were unreliable and the cards frequently mis-feed or jammed. We had special tools that could retrieve the damaged or jammed cards, hopefully with our information intact !

In the 1960s ICT introduced range of mainframe computers called the 1900 series. These varied in computing power and the models included the 1901, 1902, 1904 and 1906. I think there was a 1908 at the top end mainly for scienticic use.

Enhanced versions subsequently appeared with an A suffix and a T suffix, e.g. 1901A, 1904T etc.

The basic memory on the smaller machines was 16k words (or 64k bytes equivalent), and there were even 8kw versions. despite this apparent small memory size, quite sophisticated applications were run on the equipment and computer programmers paid great attention to the efficient use (and reuse) of memory.

Disc capacity was also very limited and similar attention to ensuring the efficient use of disk space was common. Early machines used storage on reels of magnetic tape and were then augmented by direct access devices (disks) typically with disk capacities of 1.6mb, 4mb and 8mb were the order of the day and occupied a cabinet 4 feet high.

Programming languages used were PLAN (Programming Language Assembler Nineteen-hundred) and latterly COBOL were used for the development of commercial-orientated systems. ALGOL and FORTRAN were used for scientic work.

The operating system used by the 1900 series was GEORGE (meaning to follow) and so GEORGE 1, GEORGE2S and GEORGE4 etc. were born.

After the amalgamation of ICT/English Electric/Elliott the 2900 series was introduced that could support the work of the differing ICT and English Electric regimes.

The computer hardware included the 2960, 2970, and 2980. These ran the VME and DME (emulation) operating systems.

A cut-down system based more closely upon the 1900 seies was introduced as the 2903 range, with a 2904 and a limited 2905 (which was replaced by the 2950). These ran the TME operating system, based very closely upon the GEORGE 1S operating system from the earlier range.

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LEO computer Leo 3 - origins in J Lyons and Co

System 4/70 Series 4/72 (to follow)

4100 (to follow)

In the era when the capital cost of purchasing computer equipment and operating computer systems was significant, use was made of organisations that provided such services, commonly known as Computer Bureaux. Alternative uses of these services was when they provided specialist services.

ICSL - International Computer Services Ltd

BARIC

This was a joint venture of ICSL and Barclays Bank, that provided computer services.

Out-sourcing

Some of these organisations, or their sucessors, were involved in the 1980s and 1990s trends to outsourcing of the operation of computer services. (More to follow)

Compatibility (to follow)

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A major factor in the improvemet of computer services was in ensuring compatibility with existing hardware, software and operating systems. The significant investment in the development of systems, which were usually proprietary in nature, resulted in exceptional costs being incurred if a change of supplier was contemplated. This was a form of supplier lockin that fuelled the demand for common programming languages such as COBOL and the move to lower costs of ownership afforded by open systems. (More to follow)

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