A Chapter from Design For Interaction: Rockport Books, pub July 2000

If talk is cheap, email is a steal. Hastily-written email messages can be fired out to hundreds of people with the click of a button. Instead of spending time writing messages by hand or printing typed letters to paper, email allows users to send messages almost as quickly as they are composed. As a result, nearly anyone will tell you that most of the email we get is junkăfrom advertising messages that flood the emailboxes of anyone whose email address they can get their hands on to business correspondence dashed off, replete with misspellings, fragmented sentences, and incomplete thoughts to idle chit-chat and recycled jokes.

It was the quality of email communication that inspired Tokyo-based PetWORKs to design PostPet for Son. Think Eudora meets the Tamagotchi virtual pet. This software allows users to use animated virtual "pets" to deliver email messages to other PostPet users. These pets have personalities, specific temperaments, and quirky characteristics. They also write to their owners, make friends with other pets, and keep a diary.

The explosion of email communications overlooked one important aspect of its interface designăthe intimacy of one-to-one communication. Like Marion Buchneau's homEmail, this was one of the inspirations for the design of PostPet. "I tried to introduce the old style of communicationăsuch as ordinary mail or even carrier pigeonsăinto the email world," says Kazuhiko Hachiya, the creator of PostPet. "For example, if you want to send a piece of mail to someone with feelings of friendship or love, you might choose a nicely designed envelope, lovely stamps, and so on. As much as the message of a letter, these things can express your emotions. When you receive an email message, you cannot tell the difference between a business letter and a love letter by its appearance. I wanted to design the email software so that you can express the sentiment ĺyou are a precious person to me' beyond words."

The interface of PostPet is subsequently about as warm and fuzzy as you can imagine a software interface to be. Users choose to adopt one of eight cuddly pets, which lives in a brightly furnished room in a window on the user's screen. PostPet is intentionally designed not to be the spam-spewing engine that other email clients are. The user clicks on the simple icons to compose email messages, and depending on the recipient, either has the pet or postman deliver the message. Pets can only deliver messages to recipients who also use PostPetăthe postman, a robot on inline skates, is used to deliver multiple messages and mail to recipients who aren't PostPet users. When receiving an email message from a PostPet user, the sender's pet physically travels to the recipient's "house," leaving the email on the table. The pet will then write in his secret diary, play with the user and/or the user's pet, and return home. If the recipient isn't online, the pet will wait at his house for a while (usually 12-24 hours), or leave the mail at the house before returning home.

To keep the correspondence intimate between friends and the user's interaction with the pet high, it isn't easy to send out a long string of email messages using PostPet. For instance, you cannot ask your pet to deliver more than one email message at a time. The PostPet site explains, "You want to avoid the long absence of your pet. It's also because you only have one pet and it cannot be in two places at one time."

The interface was designed to give the pets lifelike characteristics to offer personality to the messages sent and engage users in the process of sending and receiving PostPet images. Considering the more mail a pet carries, the shorter its lifespan will be, PostPet users must be judicious with whom they choose to send messages to. "The software is designed so users can use pets to send messages only their most precious friends," Hachiya explains. "This also means that a friend who has chosen to send you a message considers you one of his precious friends. The pet is a metaphor for special stamps people use to send letters. As you use more, you have less, so you choose to use it only for close friends."

Admittedly, the messages delivered by an adorable, playful pet may impress your sweetie, but not the company CEO. But PostPet wasn't designed for global email use. Instead, it was designed for the beginning Web user and those who wanted to convey more than ASCII text could convey.

"People ask, ĺIs PostPet for kids?'," Hachiya says. "This is not the case. In Japan, the ratio of male to female users is 50/50, and most users are in their 20s and 30s. We know that there are users who are kids and teens, but this doesn't mean that the software is exclusively for them. More specifically, PostPet is for computer novices who are just beginning to use email."

Rather than the business-oriented, text-only interface other email clients feature, PostPet's interface is designed to be graphics-driven, and, for lack of a better word, cute. The pet lives in a cartoon-like room rendered in bright colors and icons represent the different basic functions of the email program. The interface is created to appeal to users who may have never sent an email before by keeping the design extremely simple.

"I tried to make the purpose of this software clear," Hachiya says. "Ordinary email software is designed for business use, built to send and receive more mail in less time. But if you think about email software for private use, or for beginners, you have to change the concept."

The interface is designed to be streamlined and simple, an easy for beginning computer users to learn. "I am tired of the various different menus and buttons found in email programs," Hachiya says. "So my policy [when designing PostPet] was to delete the functions used only once a year or functions that are hard for beginners to understand."

There are no filtering or blind carbon copy features, for instance, but the functions included support the software's lighthearted concept and beginning user. "Beginners do not have many people to exchange email with, so they receive fewer emails," Hachiya says. "These people won't check incoming mail as often. So I created the software's design to make people want to check email more frequently." Users are compelled to stay online to await the arrival of friends' pets, care for their own pet, or just check in on their pet's virtual world.

Although sending and receiving of email is most fun when exchanged between PostPet users' pets, PostPet's practical needs are met with the postman. The postman can "deliver mail very quickly because he wears inline skates," according to the PostPet Web site. The Postman can be used to deliver mail when the user's pet isn't home, or when he needs to deliver the message to more than one person. "PostPet is designed to be both a game and a tool," Hachiya says. "I created the Postman to deal with problems like delivering mail when the pet is away and sending carbon copies. Of course, I wanted the program to cover basic functions. The postman is created together with the pets, because I thought developing the aspect of using PostPet as a tool was also important."

Many of the features designed as part of the PostPet interface were created so users feel comfortable creating and sending messages, especially that they are arriving at their destination. "I know email is convenient," Hachiya says. "But at the same time, people who may have never touched a PC might be worried about email, wondering, ĺIs my message getting to you?' PostPet was designed to remove such worries."

When the mail is sent and received, you receive a confirmation, in the form of your pet's secret diary, designed to be consistent with its playful interface. "When you use PostPet to exchange mail with other PostPet users, a report by your pet called a ĺsecret diary' is sent to you," Hachiya says. "The pet writes how it is treated by the recipient. When the recipient did not receive the message until while the pet's there, it records that the person wasn't there. This makes sure that you know your message was received by your friend and that you feel connected."

Perhaps the most engaging quality of the PostPet interface is that it was given a personality through the qualities of the pets Available for adoption are the teddy bear, Momo, with an intelligence level of a 3-7 year-old and a gentle disposition. Sumiko, the tortoise, has an intelligence level of your average 20-85 year-old, and is described as "argumentative and ironicăbut writes interesting emails." The mongrel cat, Furo, has an intelligence of a 7-14 year-old, is temperamental and needs a great deal of care and attention, but will write several email messages to you and your friends. The miniature rabbit, Mippi, has the intelligence of a 5-10 year-old, and is a little shy. The pets grow up, and yes, die. "Life is like that," the PostPet Web site explains. The pets have a lifespan of about two or three years.

But the personalities and qualities of the pets serve a practical interface purpose as well. When users see a visiting pet in their house, it's easy to tell who sent it, if recognized as a friend's pet. According to Hachiya, "The different pets also allow you to identify the taste (sometimes unexpected taste) of its owner." Did you peg your best friend as a teddy bear person, when he chose the temperamental mongrel cat? The pet's personalities play into the actual experience of using the software since the pets themselves sometimes send mail to you and your friends.

Since PostPet was not only a software tool, but also a game, the interface allows users to interact with the pets. You can pat (or even hit) your pet, or other pets when they come to deliver email. But beware: Too much hitting may make your pet distrust or dislike you, and it may run away from home. There's also a basic level of care you have to afford your petăyou've got to wash your pet and clean out the litter sometimes. If you neglect your duties, flies may come or your friend's pet may be disgusted by your stinky animal.

In order to keep the experience of using PostPet constantly exciting and new, designers created a series of plug-ins and options for customizing the room's interior and giving your pets snacks. When your pet gets sick, you tend to it with a sickness plug in, and you can even dabble with the mystery of the "secret" plug-in.

The most exciting part of PostPet is that the pet interacts with the user. In addition to writing in its diary or sending mail to the user or the user's friends, the pet is very resourceful. The pet can deliver greeting cards, make other pet friends, quarrel with other pets, and even fall in love. Along the way, a pet may learn weird dances or bring you back treasures from its travels. The interface allows the user to become personally invested in the software, so it becomes much more than just a communication tool.

Although it may sound hokey, PostPet bills itself as "an Internet communication tool for making friends." Whether or not you agree with this or not, you have to agree that you've got to be a little proud when little Momo composes his first email to you, his master. What has Microsoft Outlook done for you lately?