In 1944, the ENIAC filled a 20 by 40 foot room, weighed 30 tons, and used more than 18,000 vacuum tubes (e.g. Radio Tubes).
- First computer I ever saw in 1960: the IBM 705 with with a lot of "radio tubes", magnetic tapes and punched cards. The computer's memory consisted of tiny ferrite cores strung on frameworks of fine wire.
- 1967 in a research lab: Digital Equipment PDP 5 and PDP 8 - Real Time Computing - CPU with 1K or 4K of Core Memory - Programs on Teletype tapes ! Analyzing, aggregating and displaying ionospheric wind patterns. Machine and Assembler Languages.
- 1968 in a research lab: IBM 1401 - variable word-length decimal computer - Computer for small businesses: high speed card punching and reading, magnetic tape, high speed printing, stored program, and arithmetic and logical ability - still a Core Memory. Hierarchical Database. Decoding, compiling and analyzing data transmitted by a ionospheric rocket. Assembler and Fortran Languages.
- 1969 with a computer manufacturer working in R&D for high-speed peripherals: IRIS 50. Siris 2 Operating System upward compatible with IBM OS/MFT, Memory was 256 K. Machine and Assembler Languages. Minicomputer CII 10010. Machine, Assembler, Pascal, Cobol Languages.