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THE HOME INFORMATION
TERMINAL—A 1970 VIEW
Computer Science Department
Stanford, CA 94305
June 1, 2000
This article was published in Man and Computer. Proc.
Conf., Bordeaux 1970, pp. 48-57 (Karger, Basel 1972). It is interest-
ing to compare its 1970 proposals with the current situation, 30 years
later. I have decorated it with footnotes commenting on the 1970 situ-
ation and making comparisons. Some of the improvements advocated
in the paper are still yet to come. I claim quite a few prophet points
The 1970 paper
Visionaries have often proposed 1 that homes be equipped with informa-
tion terminals each consisting of a typewriter keyboard and a screen capable
of displaying one or more pages of print and pictures. The terminal is to
be connected by the telephone system to a time-shared computer which, in
turn, has access to ﬁles containing all books, magazines, newspapers, cata-
1I was the main visionary. J.C.R. Licklider was another.
I had vague hopes for a
bandwagon eﬀect by suggesting that there were a lot more. Doug Engelbart emphasized
collaborative work on time-shared computers.
logs, airline schedules, much additional public information not now kept, and
various ﬁles personal to the user.23
Through the terminal the user can get any information he wants, can buy
and sell, could communicate with persons and institutions, and process in-
formation in other useful ways. Such a system has never come about because
it costs too much, but with each advance in technology, it becomes more fea-
sible. I think that the technology of computers, time-sharing, terminals, and
application programming has advanced to the point where realistic estimates
are possible of the remaining advances necessary to make home consoles fea-
sible and useful. In this paper, I shall discuss the uses of the home terminal,
some potential beneﬁcial eﬀects on society, estimate how far we are from
a system people will pay for, and advocate some pilot projects, some stan-
dardization eﬀorts, and some laws and regulations to prevent monopoly and
secure adequate competition.
We can start with ordinary reading. To get a newspaper or book, I type
its name or number and the ﬁrst page appears. The most obvious beneﬁts
(1) I can get any document instantly.
(2) My house is not full of paper to be sorted and put on shelves and
dusted or put in the trash. Trees are not cut down, and air pollution does
not result from burning the stuﬀ.
Some immediately apparent disadvantages are:
(1) The expense. I will deal with this later;
(2) I cannot read in bed. The book-size portable terminal will come
later. A household may require several terminals or perhaps we may have to
compromise with sin and provide a hard copy terminal after all.4
There are two other immediate negative reactions:
(1) The average citizen is a TV fan and does not read anyway. In the
ﬁrst place, our system does not need so many subscribers to be economical.
2I didn’t think much about how many computers would be required. When I did, I
32000 March 2: I did not anticipate the PC or the point-and-click way of using com-
puters. The light pen was already available and it could have been used, but in fact I had
a negative attitude towards the mouse. I also expected that the user would have more
facilities for controlling the computer, e.g. to make macro operations. Point-and-click
contributed to this loss of user control although it needn’t have done so if text versions of
the actions were kept accessible.
4The hard copy terminal would have been an electric typewriter or a teletype. I did
not envisage cheap printers.
Secondly, after I have described all the bells and whistles, you will see that
even the TV fan will be tempted, and you-oh socially conscious reader–may
even want to coerce him into buying one or coerce the government into giving
him one for free.5
(2) How can you think of one more convenience and comfort when the
world will come to an end in 10 years unless menaces A, B, and C are dealt
with immediately. In the ﬁrst place, I do not think the world is about to
come to an end or even that it is getting worse, and we Americans like new
gadgets. In the second place, you will see that the new information system
will make the public more responsive to the careful reasoning of you good
guys and more immune to the blatant propaganda of those bad guys.6
In order to see the eﬀects of the new information system, suppose that all
book and newspaper information were so distributed. What changes would
At present, a newspaper or a book is a package produced by a large orga-
nization.7 In our new system, the physical production disappears allowing a
much smaller organization to put out the same packages of text and pictures.
Moreover, the user does not face a one shot decision to buy Life or Look.
He will be able to read the ’cover’ or table of contents of each and read such
items as strike his fancy, and the system will bill him for what he reads from
each source. In fact, since the cost of keeping a ﬁle of information in the
computer and making it publicly available will be small, even a high school
student could compete with the New Yorker if he could write well enough and
if word of mouth and mention by reviewers brought him to public attention.
What, then, is a publication in the new information system?
A publication is an organization that puts out a list of material it has
edited and recommends to its readers. It helps its authors produce material
that it thinks will suit the readers, and it has a ﬁnancial arrangement with
them about splitting the proceeds.8
5The Government and the socially conscious have noticed the “Internet gap” and aim
to ﬁx it. Maybe they will succeed.
6I think the 1970 doomsters were a little worse than the present day doomsters. Of
course, some of the doomsters of that day are still active, but they have toned down a
7I didn’t think of the resistance to being displaced these organizations would be able
to mount. The clearest examples of such resisters are the publication organizations of
scientiﬁc societies which are in principle non-proﬁt organizations.
8The on-line publications do not yet think of themselves in this way.
There can be a wide variety of publications of diﬀerent standards of writ-
ing and editing and diﬀerent budgets for carrying out these activities.
However, they will all be equally accessible to all readers, and the only
justiﬁcation for an expensive editorial organization will be that it can produce
a more popular package. The price of reading a package can be set by the
A reader may feel that he needs help in ﬁnding his way through the
totality of literature available to him. Various people will be eager to make a
living by providing it. A bookstore or library is a program that when called
shows the ’covers’ of publications. Reviewers will produce lists for him and
make money when he reads their lists or by kickbacks from the publishers.
’Reading advisers’ under some catchier name will oﬀer to generate lists just
for him according to a proﬁle of his interests.9.
Advertising in the sense of something that can force itself on the attention
of a reader will disappear because it will be too easy to read via a program
that screens out undesirable material.10 However, people will still want to
know what is for sale and will still want to see the seller’s story about why
they should buy it. Probably, Life will still be able to get money from
advertisers; many people will still want to know what is advertised in Life,
but those who do not want to know will be able to avoid it automatically.
Another eﬀect is the possibility of frequent revisions of articles and books.
An author can take into account new facts or other people’s criticisms, and
the revision will take eﬀect immediately. This raises 1984ish possibilities, so
it must be provided that old versions remain available. Those who suspect
the whole system will keep their own copies of favorite material in their
private ﬁles, on microﬁlm, or even on paper.
Public controversy can be carried out more expeditiously than at present.
If I read something that seems controversial, I can ask the system if anyone
has ﬁled a reply. This, together with an author’s ability to revise his original
statement, will lead people to converge on considered positions more quickly
than at present even if they do not come to actual agreement.1112
9All this has happened
10This hasn’t really happened yet.
11There are various proposals, but this hasn’t happened yet. One can imagine Bush
and McCain “truth squads” putting on their candidates’ web sites arguments against the
positions of the other guy. Personal attacks too.
122000 June 1: Today’s New York Times has an article entitled “E-Mail Messages to
the Press Have Made the Gore-Bush Race a Cyberwar” recounting how the Gore and
Famous authors will not need publishers because their loyal readers will
have the system ﬁnd their stuﬀ automatically.
To summarize: the new information system will promote intellectual com-
petition by reducing the price of entry, will permit readers to be selective,
and will allow authors to revise material until they are satisﬁed that it with-
stands criticism as well as it ever will. This should make intellectual life more
The ﬁnancial aspect of writing would presumably be as follows: a piece of
written material has a price for reading it (this price may be zero for amateur
writing, political propaganda, advertising, and for scientiﬁc journals). The
reader’s account is debited and the account to which the material belongs
is automatically credited. The reader will have the system balk at what he
considers overpriced material.
The new information system will have a profound eﬀect on buying and
selling. Sellers of movies, groceries, automobiles, plumbing services and cures
for baldness will ﬁnd it advantageous to list their wares in the information
system together with current prices and availability. The user can place an
order through the system as he can by telephone, but he can do much more:
(1) He can call on someone’s program to scan the sellers of sports cars and
propose what it considers the best deal. This program might even negotiate
with programs representing the sellers.
(2) He can tell the system whether last year’s cure for baldness worked
and get a summary of the opinions of those who bothered to record their
opinions of the cure he contemplates trying now.
(3) He can make an airplane or hotel reservation by interacting with a
program the airline or hotel reservation company has written to tell him
what is available. He need not suﬀer the delays you now get when you call
an airline or travel agent at peak hours.13
(4) Individual design and construction services can be oﬀered through the
system although this requires the development of computer-controlled manu-
facturing techniques for various types of articles. The idea is that automated
design programs can produce designs for articles meeting individual speciﬁ-
cations. Either by himself or in consultation with an expert, an individual
would use the system to produce a design and display how it would look
Bush campaigns send dozens of messages per day to reporters. I suppose this is a partial
realization of my 1970 prediction.
13All this has happened.
and possibly how it would perform. Candidates for individual design include
clothing, furniture, boats, electronic equipment, houses, and even cars. The
system would then produce the instructions for controlling machine tools,
fabric cutters, and also printed instructions for the hand parts of the oper-
ation. In general, it should be possible to make single objects at little more
cost than present mass produced objects. In some cases, there would even
be savings, because mass production requires estimates of demand that are
often wrong resulting in inventories that are expensive to sell or even have to
be sold at a loss; the cost of this is made up by a general increase in prices.14
There are many more useful services that can be oﬀered through the
new information system and again the system is conducive to competition.
Writing and storing a program and announcing its availability can be a very
low capital operation, and the system can collect whatever price has been
set for its use.
We could go on listing services that would come to be oﬀered in a fully
developed system, but now we shall list some services to smaller groups of
users that are cheaper to provide and which will help get the system started.
(1) Calculation and facilities for writing, running, and debugging com-
puter programs: This does not interest the general public much, but it is
the present bread and butter of the time-sharing service bureaus that will
grow into the new information system. At present, these service bureaus
oﬀer a very convenient way of doing small scientiﬁc and engineering calcula-
tions, but do not oﬀer reasonable prices for big computations, and are only
beginning to oﬀer useful services to business ﬁrms.
(2) Editing: Anyone who writes (writers, journalists, scientists, advertis-
ing men, engineers and students) will beneﬁt from using an editor program.
It allows easy revision, can be made to check spelling, grammar, and punc-
tuation, and will produce justiﬁed or other forms of elegant output and also
(3) Filing: Keeping personal ﬁles in the computer has great advantages
once documents can be entered without retyping them, either because they
have been prepared in a computer readable form or because a suitable page
reader is available. Namely, one can retrieve any document on the basis of
its characteristics without having taken the trouble to ﬁle it properly in the
(4) Education: Computer-aided instruction (CAI) has advanced to the
14This hasn’t happened yet. Maybe it will.
point that a number of courses or aids to traditional courses have been devel-
oped and have been shown to be useful. The main obstacle to the widespread
use of CAI is economic, but new developments in display technology and com-
munications give a reasonable probability of cost-eﬀective systems within this
decade. There is no special problem in having these systems available in the
home as well as at school. This would be aided by standardizing course writ-
ing languages. Again, we should try to stimulate competition by encouraging
the oﬀering of courses in particular subjects independent of the schools.15.
The development of such a system is probably inevitable (unless it is for-
bidden by law) as soon as costs come down to the point where it is proﬁtable
for time-sharing service bureaus to oﬀer services to individuals. However, fa-
vorable policies will bring this about sooner and will make the eﬀects better.
The main danger to be avoided is the creation of services of limited scope
that through some avoidable feature cannot be expanded to provide the ser-
vices mentioned here and many more.16 Another problem is to avoid mo-
nopolies; the intrinsic nature of the system permits any person who can
write computer programs to compete with large organizations in inventing
and oﬀering imaginative services, but one can worry that the system might
develop commercially in some way that would prevent that. In general, we
should try to develop information services in such a way as will enhance the
individuality of its users.
Between us and the home information system lie a number of problems;
some in developing suitable low-cost terminals, some in programming tech-
nology of time-sharing, some in the economics and politics of communication
systems, and some in the attitude of the public and government towards
innovation. In the following sections we shall discuss these problems.
How we Get There from Here
one can add a display console with keyboard to our laboratory system for
about $ 700, but to add another part on the system so that the number
of consoles active at one time is increased by one costs about $ 2,500. A
reasonable display console that can be located at the end of a telephone line
now costs about $ 10,000. These consoles are adequate for any of the services
15All these have happened
16Minitel in France was such a service, and the promoters of set-top-boxes are trying
for such limited devices. I think they’ll fail, and this is shown by the fact that companies
like Ford are oﬀering their employees PCs and not set top boxes.
mentioned in the previous section, although for reading purposes, it would
be desirable to be able to display more than 35 typed lines at a time.17
In my opinion, the cost of an adequate display terminal that can be
located at the end of a telephone line will be in the $ 500 to $ 1000 range
by 1975 even without a market of the size of the potential home-terminal
market. The business, engineering and science, and government markets will
be large enough and price sensitive enough to bring this about.18
Another contender as a terminal is the plasma panel, but the above esti-
mates are based on CRT terminals with a mini-computer and an integrated
ing rapidly but in a rather disorderly way because of the multiplicity of
requirements of the diﬀerent applications. Some applications such as credit
veriﬁcation require very low-cost short communications with turn-around
times of seconds. Others require very low cost per bit but can stand delays
of minutes and hence are candidates for low performance store and forward
systems. The terminal systems require long holding times, short response
times, and much higher transmission rates from the computer to the user
than in the other direction.
For the purposes of the home terminal, the speeds of transmission over
present unconditioned voice-grade circuits are a bit too low for such appli-
cations as reading. 1200 bits per second would take 20 sec to transmit a
typed page and about 4 times that for a page of a dictionary. Eight times
this rate is obtained over conditioned voice-grade lines, and this might be
barely adequate. Perhaps a better bet is the transmission facility planned
for the picturephone service now being introduced experimentally, but the
cost of this service for long holding times is not yet determined. The most
economical system might be a specially designed store and forward system
conﬁgured to give fast turn-around for short messages.20
Whether such a service will be made available depends on political as
well as technical factors. For example, if on the basis of present plans, the
17Remember that those numbers represent a larger fraction of a person’s income than
a PC does today.
18It didn’t happen that soon, because the terminals were too elaborate.
19Plasma panels and the like are still an also-ran. The LCD panel didn’t exist then.
20The Arpanet met this speciﬁcation around that time, but its use was limited to labo-
ratories supported by DoD. It gradually expanded till it became the Internet.
digital communication market is divided by regulatory action among AT&T
and its potential competitors, it might turn out that no one is obliged or
even allowed to oﬀer the service required for home terminals at a reasonable
home terminal at a reasonable cost, provided computer conﬁgurations are
optimized for the purpose, provided reasonable load factors can be obtained,
and provided there are reasonable economies of scale. Unfortunately, IBM
computers are organized in such a way that time-sharing is very expensive
because of their interrupt-structure, their expensive terminal multiplexors,
and their dedication to the archaic half duplex method of communication.
The other major computer manufacturers such as CDC, General Electric,
and Univac are not in much better shape since they oﬀer for time-sharing
machines that were optimized for other purposes. Smaller companies like
DEC are in a somewhat better position. However, none of these diﬃculties
are permanent, and better organized computers may be expected once the
factors in computer design that make for good cost-performance in time-
sharing become clearer to the manufacturers.21
The present magnetic disk storage units are a bit marginal in cost eﬀec-
tiveness for use with home terminals. Thus storage on the new IBM 3330
disk would cost a user about $ 0.03 per month to store a typewritten page
making storage of extensive personal ﬁles expensive and private copies of
books at $ 5 to $ 10 per month prohibitively expensive. This would not be
too expensive for national libraries, but it would be economically very diﬃ-
cult to get enough readers to support the storage of books on magnetic disk
ﬁles in the near future.
Fortunately, much larger ﬁles are becoming available. The laser ﬁle made
by Precision Instruments Inc.
is claimed to store a trillion bits and costs
$ 1,000,000. This comes to about $ 4 per book which is reasonable even
for single copies. Mass production of such ﬁles will reduce the cost even
21The archaic features of IBMs computers lasted much longer than I expected.
22No-one, not even IBM, imagined how much that same old magnetic disk technology
could be reﬁned—mainly by IBM. This made the laser ﬁle an also-ran. It is now much
cheaper to store a single copy of a book on your disk ﬁle than on your bookshelves. You
still (2000 May) can’t get the books you want unless they are among the more than 11,000
books in John Mark Ockerbloom’s catalog of free on-line books, which have been entered
well-developed in that cost-eﬀective systems have been written, but there is
still a lot of chasing of willow-the-wisps, and quite bad time-sharing systems
are often produced by otherwise competent ﬁrms. Before the programming
required to oﬀer the services mentioned in the ﬁrst part of this paper can be
accomplished, some further advances need to be made including at least the
(1) the interactive and ﬁle reference aspects of programming languages
and time-sharing systems need to be standardized so that an interactive
system written in one system can be used in another that uses diﬀerent
hardware and a diﬀerent time-sharing system. Without this it will be very
expensive for new user services to get large markets unless some particular
timesharing system gets a monopoly;23
(2) a system needs to be developed for representing text in a computer
that will include the full variety of alphabets, type fonts and character sizes
and also be adaptable to diagrams, drawings and photographs. The consoles
also have to be adapted to this variety of styles. This is an ultimate require-
ment; much can be done with texts that are just regarded as sequences of
(3) the biggest task, however, is the application programming itself.
of time-sharing services is that it is not a natural monopoly. Communication
is cheap enough for teletype-based time-sharing so that with local multi-
plexors, time-sharing bureaus can compete all over the United States.
principal, it should be possible to have world wide competition. The ma-
jor force that might tend to reduce competition is the exclusive possession
of proprietary programs or ﬁles. Therefore, it is desirable to separate the
ownership of programs performing services from the ownership of the service
bureaus themselves and to encourage enough compatibility between diﬀerent
time-sharing systems so that the owner of a service program could provide
it on a number of machines.
It is also important that important ﬁles be
accessible and modiﬁable with suitable protections by actions initiated on
by various enthusiasts. The catalog is at http://digital.library.upenn.edu/books/. When
I want to read such a book, I read it via Netscape rather than copy it to my own disk.
23This is the situation today including Microsoft’s attempt to maintain a monopoly.
24This still hasn’t happened in a uniform way. It’s coming. It’s coming.
other machines than the one that maintains the ﬁle.25
sive systems for probably another 5 years. In the meantime, research and
development should be undertaken in the following areas:
(l) standarization of the interfaces of time-sharing systems and their lan-
(2) experimentation with services. At present, it is very diﬃcult to get
support for development of generally useful services unless either it can be
claimed that disaster will result from failure to support the activity or that
the supporting organization will itself make a proﬁt. This political fact is
one of the reasons for the concentration on military technology in the recent
(3) research aimed at devising ways of coordinating the great variety of
time-sharing services into a mutually communicating network. Neither suf-
ﬁcient understanding nor suﬃcient political or commercial force is available
to cause the development of timesharing services to proceed according to a
uniﬁed plan. Nevertheless, computers are ﬂexible enough so that originally
incompatible systems can be made to communicate and use each other’s ser-
vices. Experiments with the ARPA network that provides communication
between US Government-sponsored research computers will provide useful
technological community and also the public aﬀairs community regarding
technology and the human future. There were a few technically competent
but rather narrow surveys of the state and prospects of particular tool areas
of technology. There was much random doom-saying and denunciation of
currently fashionable whipping boys. There was a fair amount of opinion that
certain things should not be done. There was an almost total lack imaginative
discussion of the opportunities technology oﬀers us to improve human life.
This lack was especially notable in those individuals and organizations that
25The prevalence of personal computers has accomplished the separation between own-
ership of hardware and the development of programs.
26It didn’t happen and isn’t happening.
27In 1972 the Stanford AI Laboratory, with most of the work done by Martin Frost,
built an experimental online news service based on the Associated Press news wire. We
never attempted to expand it beyond the AI Lab computer. It lasted till 1989.
are supposed to be professionally concerned with the matter. This essay
represents a small eﬀort to redress the balance.28
28This was a particularly bad conference in the above respects, but conferences domi-
nated by equally bad attitudes persist to the present day.