W6D2

W6D2

Software

Computer (hardware)

1010 0110 1011 11001101 1111 0000 10100110 1010 1110 0001

Add 20,22,34

W6D2

Memory

Magnetic core memory

W6D2

Memory(DRAM)

W6D2

Memory(DRAM)

W6D2

Software

Computer (hardware)

1010 0110 1011 11001101 1111 0000 10100110 1010 1110 0001

Add 20,22,34

W6D2

Running programs

Early computers:• programs on perforated cards• users installed tapes & cards…• signup sheets!

W6D2

Running programs

Things got a bit better:• operator installed punch cards in batches (less time organizing, more computing time)• a computer program controlled the execution of user programs (jobs)• users had no direct interaction

W6D2

Running programs

The PDP-1 operating system's timesharing ability made interactive access to computers economically viable by allowing various users to share the computer simultaneously. Shown here is the PDP-1 installation at BBN.

W6D2

Running programs

System programs:Operating Systems

User programs:Applications

W6D2

Hard disc

IBM DiscStorage System(1961)

W6D2

Creating programs

W6D2

Source code

W6D2