You know the feeling, it’s raining outside and you’re at work facing the gray wall with the gray windows behind you. You check Twitter and there is your mate’s latest; ‘We’re having a great time on the beach’ and there’s the photo of said beach with plenty of blue sky. Looks lovely doesn’t it?
If you think of a tweet on Twitter like that; a short line of text and a glossy image, then there is an old-school parallel to it and that is the good old postcard. No idea if anyone sends them anymore, but they did the same thing as the holiday tweet does now, they give you a brief glimpse of the place and a personalised, fairly non-informative, line of text. The main difference is that you would read a postcard after you came home from work rather than sat at your desk.
Twitter have recently announced that they are looking at ways of relaxing the character limit on their tweets, this prompted me to think about old-school parallels for Twitter and I’ve also been looking at where the 140 characters limit came from, and it’s a very interesting bit of technical history.
Twitter and SMS
A tweet isn’t just 140 characters, it’s 140 characters and the name of the person who is tweeting. The latter has 20 characters allotted to it and so the total count for a tweet is 160 characters. So why 160 characters? 0ne thing l could point to is that it’s 2 x 80 and 80 was a key number in the early days of computing as it was the number of columns on a punched card, but this idea would only really be relevant to older programmers who have some legacy in that world of cardboard computing.
It turns out that when Twitter was getting started they had the idea that people would be able to tweet from their phones by text message and, as this was a time before smart phones, those text messages were restricted to 160 characters.
SMS and postcards
So why then was 160 characters chosen as the length for text messages? In the early days of text messages or Short Messaging System (SMS), the boffins that were laying the groundwork for the future of mobile telephony had to come up with a limit. There was a general consensus that a system for short messages would be really useful, just look at the success that the telegram service had enjoyed in years gone by. The question was; ‘How short is short?’. As part of the decision making process one of the design team sat himself down in a hotel room with a typewriter and tried typing typical messages that people might want to send. In the end they came up with 160 characters. With much pushing and shoving of the underlying technology they managed to achieve this by limiting the character set
Was it a good guess? User testing was in its infancy and setting up a test of the suitability of a new communication medium is a very tricky thing to do indeed, especially one that will be a paid service.
In the end the decision to go with 160 was supported by looking at two examples of short communications. One was the business oriented Telex system. Although it was a system that had no length limits the messages were generally short. Things like confirmations, questions, quick answers etc. This fitted in well with the proposed 160 character limit. And the second short communications example they looked at? It was from the personal communication domain. Postcards! They discovered that the average message on postcards was less than 150 characters.