If you have enabled keyboard shortcuts in Gmail, you may have noticed that pressing the J key selects the previous (older) message in your inbox while the K key moves you one message up to a newer conversation.

The same j & k keyboard shortcuts can be used for navigating items in Google Reader, for moving between tweets on Twitter.com, and it even works with Tumblr.com.

So why do developers commonly assign the k and j keys for moving up and down respectively and not any other key combination?

When Bill Joy created the vi text editor for Unix, he used a ADM-3A terminal and its keyboard didn’t have any dedicated arrow keys (see illustration above). Instead the keys h, j, k and l were inscribed with arrow symbols and these keys, in combination with the CTRL key, were used for moving the cursor on the screen.

The keyboard layouts have changed (they got dedicated arrow keys) but the same j & k keys are still popularly used for moving the cursor up and down inside the vi text editor. And since most developers have their roots in the Unix world, they implemented the same shortcut inside their web apps.

Wikipedia has more details on the history of vi and the HJKL keys.

This story, Why do Gmail and other Web Apps use j & k Keys for Navigation?, was originally published at Digital Inspiration on 01/02/2012 under Keyboard Shortcuts, Internet.

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Do you have an old mobile phone, like the Nokia 1100, that has no browser and can do little more than make phone calls? Or are you stuck in some remote place where there’s no Internet or no other form of data (EGDE/GPRS/3G) connectivity is available?

Not a problem. You can still use your Facebook account in India by dialing *325# (or *fbk#) from your mobile phone – this service requires no data plan or Internet and it will even work on phones of the Stone Age. Here’s a quick tour:

Use Facebook without the Data Plan

Facebook India has partnered with Fonetwish to bring Facebook on every mobile phone without requiring any apps or even the Internet.

You dial the *325# number, then enter your Facebook username and password and you are in. You can then send number based commands to access various features of Facebook, chat with friends who are online, add new people to your friends list, and more.

I played with the service for some time and it was a nice experience overall. If there were a Unix-like shell interface for Facebook, it would be much similar. Fonetwish says that this service is currently available for Airtel, Aircel, Idea and Tata Docomo users in India.

It may be too much work to read your Facebook news feed stories one by one but this is a good option to quickly update your Facebook status or for chatting with friends who are online. The price is reasonable too – you just have pay a subscription fee of 1.00 per day for unlimited usage.

Related: If you have an old mobile phone, you can search Google by SMS without requiring a data plan.

This story, Access Facebook on any Mobile Without the Internet, was originally published at Digital Inspiration on 12/01/2012 under Facebook, India.