NB: this post is a continuation of “The city as interface (part one)“, published on 6th August 2010

The modern city is a built environment whose purpose isn’t just to house and feed us. It offers us access to both information and capability, and it has evolved ways to help us to understand and navigate its considerable complexity.

In this sense the city is an interface and the people within it, residents and visitors alike, are its users. But the city is not a passive interface. It is a highly responsive one which evolves continually over time.

This constant development is the result of many social and economic factors which I’m not going to explore here. Instead, I’m going to look at two mechanisms that help cities become more effective the more they are used – adaptability and feedback.

Multiple layers of experience

Many modern cities are so complex that even if you spend your whole life in one you’ll never fully understand it. London’s taxi drivers experience physical changes in their brains after spending years memorising its street map, which is just one of the city’s many layers. So what hope is there for the visitors experiencing it for the first time?

The fact is that cities are not allowed to be complicated. If they can’t successfully accommodate outsiders, the outsiders won’t stay, and the city won’t be a city for much longer. The city must therefore be adaptive – it must offer a range of experiences to its users based on the extent of their familiarity and expertise.

A first-time visitor must be able to access the features they need to use without being confused and obstructed by those they don’t. Cities achieve this by using transport networks to negate their geography, or by having certain locals (such as London’s taxi drivers) learn the intricacies so that others don’t have to.

Locals have a better background knowledge of the city so, like power users of a computer system, most things they do become habitual, almost instinctive. But the interface of the city still accommodates their needs. An example of this in many cities is the bus system, which tends to be optimised for locals at the expense of outsiders.

Computer interfaces have similar ways of providing a layered experience to users, and the less specialised the interface the more layers there are. The Nintendo DS has a specific purpose, so its interface has very few layers. More advanced users might configure the clock or change wireless settings, but there’s little else to do apart from load a game:

Systems like Mac OS or Windows are very different. There is a “welcoming” layer aimed at newcomers in which commonly used applications and features are highly visible, and many people use an OS for years without moving on from this layer. But under the surface there are other layers – the registry, the command line, the process list – which can seem intimidating but are essential tools for other users of the system.

Multi-purpose interfaces fail if they intimidate new users with difficult features, and they also fail if they force experienced users to wear kid gloves. A strong interface, like a successful city, will accommodate both user types and all the grey areas in between.

Becoming a part of the interface

When we “use” cities,  they use us too. They incorporate us into the experience offered to other people – we become part of the show. Here’s an example.

One morning last week I was walking to my local tube station. Before long I started to sense that something was wrong. As I got closer to the station this conviction grew, and eventually turned out to be correct: the station was shut and all hell was breaking loose.

How did I know there was a problem? I hadn’t received a text alert or seen any signs. Instead, I’d used something that many city dwellers use all the time, often without knowing – the city’s feedback mechanism.

On that morning I noticed, almost subconsciously, that there were more people than normal on the pavements. Several people apparently dressed for work were walking away from the tube station, or looking confused and directionless. It was subtle but noticeable, and as I noticed it my behaviour changed also. Before long I was part of the feedback mechanism, part of the crowd whose behaviour informed others that the tube station wasn’t working.

The city is full of behavioural patterns that we observe, follow, and unwittingly learn from all the time. Their importance can’t be overstated. Remove the flow of humanity and the city becomes a surreal, frightening place, a sensation that was exploited by the film 28 Days Later.

The inherent eeriness of an empty city

It’s only recently, in the age of social software, that computer interfaces have developed the ability to emulate this sort of feedback mechanism. Older interfaces couldn’t reflect aggregate user behaviour in the experiences offered to individual users. But in today’s online environment things are different.

When you browse Amazon, your navigational choices are used by the system to influence the choices that subsequent visitors will see. When you watch a video on Youtube, you add to its view count in a way that’s visible to others. And if you removed the flow of users from Twitter or Facebook you’d be left with literally nothing at all.

Modern interfaces are starting to use feedback mechanisms similar to those that cities have been using for centuries. Our use of the system affects the system, and affects how others experience it too. The dividing line between the user and the interface becomes a blur.

Conclusion

Analogy is a slippery slope. Successful interactive interfaces may well have lots in common with successful cities, and we may well think of the city as an interface, but the analogy shouldn’t be taken too far. Cities have spatial constraints that computer systems don’t share, and they tend to be the result of long-term evolutionary design processes rather than centrally directed ones.

But even with these differences in mind there’s a lot we can learn from how cities function as interfaces. Cities solve problems that interactive systems have only recently become sophisticated enough to have. If we can understand those problems well enough, the modern city can be a treasure trove of inspiration and insight to designers of future interactive systems.

Dirk Kneymeyer of Involution Studios writes on his blog about how he’s losing faith in UX. He’s reacting primarily to an article by Whitney Hess characterising start-ups as being focused on the what rather than the who, why or how.

One of Kneymeyer’s central points is that product strategy and user experience are ultimately different domains, and that user experience professionals aren’t typically the most qualified people to define product strategy.

I’m inclined to agree with that point. Because user experience, as an emerging discipline, is still consolidating many of its techniques and methodologies, there’s an exuberant tendency that often sees UX extending its dominion into other areas. This can sometimes be appropriate – it’s a good thing, for example, that user experience practitioners increasingly concern themselves with content strategy –  but in other cases it blurs the definition of what user experience is, and it can sometimes come across as disrespectful towards professionals in other fields.

There is an obvious overlap between user experience and product strategy, centred around scenario planning. But even this exercise works very differently in a user experience context than it does in a strategy & planning one. Scenario planning in a strategic context involves having to discard or gloss over some issues that are central to ‘traditional’ UX, while becoming obsessed with details that a typical UX project would leave to one side.

My experience of working with people who specialise in product strategy is that it’s a well developed field in its own right. Yes, it can learn from experienced UX professionals (and it knows it can – I’ve noticed increasing interest in UX from product & business strategy teams in the last two years), but the opportunities for learning are reciprocal and not just one-way.

In Responsive Environments: Architecture, Art and Design, writer Lucy Bullivant refers to urban environments as “interfaces in their own right”. Reading this, I found myself wondering – do modern cities function as interfaces? If so, how? And can designers of interactive systems find new inspiration by thinking of cities in this way?

“The map is not the territory”

By expressing functionality in a way that’s more suited to our needs, interfaces help us understand and act upon devices and systems that could otherwise be confusing. They’re most helpful when something’s function is not directly expressed by its form: a pencil doesn’t need an interface, but a pencil sharpener might.

From this perspective, it could be said that the Tube map of London is an interface for the city. After all, it abstracts the tangled system of London streets into a neatly organised network of straight lines, making its complexity manageable even to tourists. But this is incorrect. It’s the tube network itself – not the Tube map – that acts as an interface for London.

This is because the Tube map isn’t actually an abstraction: it might distort geography, but it represents the network’s structure faithfully. The network itself is the abstraction, the layer of navigation that helps us forget the confusing mess of streets and avenues above ground. It is interactive: we can use it. The Tube map is an ingenious visualisation of that interface, but is not an interface in itself. As Alfred Korzybski said, the map is not the territory.

So when we think of cities as interfaces, we should go beyond thinking of visualisations and maps and focus instead on how the physical make-up of the city facilitates its use.

The problems cities are required to solve

All human settlements have certain things in common. Places for people to eat and sleep, and facilities for producing food, materials and so on. Another is navigation. Even the smallest hamlet has a navigational or wayfinding role to play, acting as a landmark for passing travellers with no interest in local happenings.

These three basic roles – habitation, production and navigation – apply to almost every place that people live. But in larger settlements additional uses are encountered. A traveller passing through a town might look for medical assistance, or establishments providing food and accommodation. In a larger town, there might be thriving local industries, academic institutions, working artisans.

As settlements grow in size these roles explode in number. These in turn attract ever more visitors, many of whom establish businesses and institutions and therefore add to the range of uses on offer. After a while the vast size and complexity of the settlement begins to pose a new challenge: how can anyone possibly understand everything that’s happening?

It’s in response to this challenge of incomprehensibility that the “interface” of the city has evolved over time.

The designed environment

As cities grow, they effectively become designed environments. Rivers are submerged beneath roads, hills and valleys are smoothed over, landfill and burial sites override the natural topography. When we’re surrounded by city we’re in an environment shaped (consciously or not) by humans, an environment whose very structure has a function: to point us towards the roles, uses and amenities that the city offers.

If the city’s environment fails to do this well, the city itself is failing. Visitors looking to sell won’t locate the businesses willing to buy. People needing help won’t know where to look for it. The “functionality” of the city will go undiscovered and the city won’t be used. The goal of the urban environment is to make the city’s functionality discoverable to its users.

Patterns

The structure of a city, then, has objectives in common with “conventional” interfaces – to help users locate and utilise underlying capability. In a city, this capability could be anything from acquiring a visa to buying a rare, imported album. In a computer system, it might be turning the wi-fi antenna off and on. But in cities, the number of capabilities is significantly greater. So how do cities help us make sense of them?

One way – which can also be seen in interactive interface design – is through the presence of patterns which help make cities comprehensible. As we enter an unfamiliar city from its outskirts, we will probably know without being told when we’re entering its central district. Other patterns are more specialised. Record collectors visiting unfamiliar cities will often find record shops easily, thanks to the patterns that “signpost” those sorts of areas.

Just as computer interfaces use patterns to accommodate the mental models of their users, cities use them to reward familiarity: the more cities you know, the easier it is to find your way around the ones you don’t. And there’s a functional importance too. These patterns often develop into localised “clusters” within which industries or disciplines are closely concentrated, such as the cluster of media businesses around Soho or the legal profession’s concentration around Chancery Lane.

Grouping related controls in Windows 7

When this happens the city isn’t just making itself easier to navigate, it’s making itself easier to operate, just as an interactive system is more usable when similar features are placed near one another. And when cities are easy to operate, all constituent parts – from local businesses to visiting strangers – feel the benefits.

So far we’ve explored how the structures of successful cities share some of the conventions of successful interfaces. But real interfaces are interactive – they aren’t just static maps and informational aids. When we do something with them, we receive feedback and response. The second part of this post will look at how the city provides feedback and how, when we  use a city, we become a part of the interface ourselves.

This is part one of a two-part post. Click here for part two of this article

Since the launch of the iPad, hubris and hysteria among technology commentators has been gradually increasing. The device is the future; Rupert Murdoch thinks it’s the saviour of journalism; it will change the world; it “can replace any real-world object you own”.

One notion that I take exception to, however, is that the iPad signals the death of the keyboard and that touch interfaces are destined for ubiquity.

Now, I’m no technological conservative – I’ve been using touch-screen phones since before the iPhone came out. But I think a more fundamental point is being missed here, which is that the roles computers play in our lives are multiplying greatly.

Computers used to play a relatively limited set of roles which could be supported with a common set of interface models, mainly centred around the keyboard and the mouse. The keyboard & mouse setup worked when the computer operator was sat at a desk, had to enter lots of data from a large character set, and needed direct access to many (maybe even several hundred) on-screen controls offered by their applications.

Today, not every computer user is sat at a desk and in the need state described above. Computer users might be on the other end of a phone line from the machine itself, operating it through a (notoriously infuriating) voice interface. They might be delivering a parcel and collecting the recipient’s signature using a handheld computer’s (notoriously infuriating) pen interface. And of course the computer user might be using a personal device like a smartphone, which needs to be small and light and whose functions don’t require the sort of  intricate and precise interactions supported by the keyboard/mouse combo.

But this doesn’t change the fact that some computer users will still be in situations where the keyboard and mouse paradigm is appropriate. Therefore the keyboard will not die.

What things like the iPad illustrate is that we are using computers more than we used to – in a wider number of contexts and for a wider range of reasons. They don’t replace what we already have, they’re just a new addition to our collection of tools.

I’ve been trying to codify some guidelines for writing for the web recently, and came across this study (PDF) by Wichita University’s Software Usability Research Laboratory in 2005.

The study involved 66 graduate students with either normal or corrected vision being given a short story to read online. A preliminary reading test was carried out on participants so the study could predetermine their reading speed. Different text layouts were used, such as multiple column, full justification and so on. Study participants were tested for both reading speed and reading comprehension.

• Reading speed: Multiple-column layouts impaired reading speed when text was left-justified. However, left-justified text was read more quickly in a single column layout than full-justified text. The highest reading speed was 269.33 words per minute for two-column, full-justified text.
• Reading comprehension: No significant variation was found across the different text formats.
• Fast versus slow readers: Faster readers benefited most from the 2-column, fully-justified layout. Slow readers benefited from 1-column, left-justified text.

The study was perhaps limited by the fact that the participants, as undergraduates, were heavier readers of online text than the average member of the population. I’d be interested to see if any similar studies have been carried out with a larger sample size, broader age range and a more representative mix of internet ‘natives’ versus internet ‘newbies’. Does anyone know of any? If I find some I’ll post them here.

This series of articles from Rob Tannen at Designing for Humans discusses how a knowledge of ergonomics can be increasingly helpful to people working in interaction design.

Ergonomics considers the suitability of physically extant products to the human form in all its varieties. As a result it’s not historically been very relevant to interaction designers, who have worked in a more abstracted space than those who design chairs, computer mice, monitors and keyboards. But Rob Tannen argues that the advent of ubiquitous computing and the resulting diversity of form factors (netbooks, phones, touchscreens, kiosks, etc) require interaction designers to develop their understanding of this field.

The three-part series of articles makes for easy reading, an interesting and engaging introduction to the field. It’s also rich with links to more rigorous and in-depth materials for those who want to explore it further. If you want to be able to talk knowledgeably about anthropometrics, satisficing and the flaws of the Proctrustus approach, you’ll find Rob’s writings more than helpful.

My friend Lindsey sent me this link earlier on today. It’s a video exploring a future user experience concept, developed by Adaptive Path for Mozilla Labs.

Jill looks at the New York Times website

In the video Jill, the principal user, makes use of a number of futuristic interface devices to:

• Interact with a friend while browsing
• Extract and manipulate data sets from within websites
• Navigate through a vast collection of bookmarks using a 3D interface
• Migrate her browsing experience seamlessly from desktop to mobile devices

It’s a bit like MacOS X

I initially found myself wondering, is the future really going to look so much like Mac OS X? But looking past the visual treatment, there are some strong concepts here. I particularly like the ability to extract and manipulate data from web pages, the near-removal of the browser interface, and the utilisation of the 3D interface to convey the age of bookmarks.

That said, not everyone agrees with me – I’ve had a few conversations today about these ideas and there isn’t really a consensus among the people I’ve been talking to.

The Z-axis is used to convey the age of a bookmark

Is 3D ever really going to enter the mainstream as a means of web navigation? I’ve always been quite sceptical, to be honest. It comes down to incentive – if there’s a serious benefit to be had from learning unfamiliar and complex interfaces, then people will do it. People learnt how to use Myspace, after all!

So, what would have to happen to make us want to learn new, complicated, 3D web interfaces?

Well, the web (along with our own slice of it; our bookmarks, our browsing histories, our social networks etc) is on its way to becoming unmanageably large. Past a certain point, there may be a real benefit in migrating to more sophisticated – but more complex – interfaces.

The standard methods of searching and browsing may still be usable, but woefully inefficient; like running a modern computer with only a command line interface and no GUI. Achievable, but insane.

The web is growing exponentially – its size in five or ten years’ time could present us with unique problems and challenges. Some of the ideas in this concept video shed some light on how we might solve them. But what are those problems and challenges going to be? I’m probably more interested in them than I am in the solutions.