The Case of the Missing Tab

One of the things we noticed when we first started doing some rigorous usability studies with Word is the way people used the tab key. It’s a holdover from typewriter days: you want to indent a line of text, so you hit the tab key a few times. It’s one of those learned behaviors that, over time, have become rather difficult to unlearn. One could probably start a whole field of cognitive science built around this issue of mapping old behaviors from one technology to a newer, yet similar, technology—that is if academia hasn’t already started one.

This kind of thing presents a problem to those of us who develop the newer technology. How do you help users take advantage of the new paradigm that the new technology presents without asking users to give up their learned behaviors? The case of the tab key is classic. Not only does a Word Processor offer fine control over tab stops, but it also provides an alternate way to achieve the result one used to use the tab key for: paragraph indents.

One might ask whether this is a problem at all. After all, we could simply let users use the tab key when the really want an indent, and let them climb the learning curve about tab stops and indents in a modern word processor. And, to a certain extent, it wouldn’t have been quite so much of a problem had we been building a word-processor from scratch. The problem stemmed, in part, because Word already had some behaviors with respect to indents and tab stops. For users who hadn’t climbed that learning curve, using the tab key to create indents often produced results they didn’t really want.

I’m not going to enumerate specific scenarios, primarily because I wasn’t intimately involved in studying them. I’m likely to leave out key aspects if I try to discuss them. If one of the folks involved happens to read this, perhaps they can add more insights into these specific problems.

So, we had a problem, and it had a deceptively simple solution. This is exactly the kind of problem Word’s Auto Formatter was designed to solve. The fancy name for Word’s Auto Formatter is a “rule-based inference engine,” which really means that it’s like pattern matching on steroids. It takes into consideration the current state of the document, and interprets various keystroke input sequences in terms of a set of rules. It’s designed to work very fast, so that users don’t notice any effect on typing performance.

Using the Auto Formatter to solve this problem turned out to be not as simple as it first seemed. Obviously, there are times when the user really wants a tab stop, not an indent. How do we know? Well, we tried several different ideas, and figured out that there were three basic cases that we needed to think about. These involve having an insertion point a) at the beginning of an empty paragraph, at the beginning of a non-empty paragraph, at the left-hand edge of a line that’s somewhere in the middle of a paragraph.

Note that this discussion does not pertain to headings and outline levels in Outline View. There is an entire set of behaviors associated with the tab key in Outline View that do not involve the Auto Formatter at all. For a discussion of tab-key behaviors in Outline View, go here.

The empty paragraph case turns out to be the hardest. In that case, trying to infer intent ends up being so complicated that you can’t write a rule set that captures the possibilities. So, we left that one alone. When you press the tab key in an empty paragraph, Word will always insert a tab character.

When the insertion point is at the beginning of a line somewhere in the middle of the paragraph, users almost always want the paragraph to be indented, so that’s what Word does. This can present a problem, but there’s a workaround (more on this later).

If you’ve already typed up a paragraph, and put the insertion point back at the beginning of that paragraph, then there are really two possibilities. If you’ve set a tab stop, even if it’s on one of the default tab stop locations, Word will insert a tab character. If you haven’t set a tab stop, then Word will apply an indent to the first line of the paragraph mark.

To summarize these rules, if the insertion point is:

1.      In an empty paragraph–always inserts a tab character;

2.      In the middle of a non-empty paragraph–always indents the whole paragraph; and

3.      In the first line of a paragraph:

3.1.  If there are no tab stops set, then indents the first line of the paragraph; or

3.2.  If there is a tab stop set, then inserts a tab character.

The most common case where Word is likely to be wrong is case #3, so the auto-recovery feature in Word 2003/2004 allows you to convert the auto-formatted indent back to a tab.

We hadn’t known it at the time, but it turns out there’s an interesting case involving rule #2. Suppose you have a paragraph, but have inserted manual line breaks. If you put the insertion point at the beginning of one of those lines, Word still thinks that you’re in the middle of a paragraph, though, typographically, it looks like the line is its own paragraph. Hitting the tab key at that point won’t insert a tab character. It will indent the whole paragraph.

In this case, there is a workaround. In fact, the workaround will work under any circumstances where Word interprets the tab key as an indent. When you press Ctrl-Tab, then word always inserts a tab character.

Lastly, you can turn all of this off via Preferences/Edit and unchecking Tabs and backspace set left indent.



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Comments (13)

  1. Rune says:

    Interesting to read this, because the auto-formatting in Word has always been kind of a mystery to me 🙂

  2. <rant>

    It is interesting to read about this as the autoformatting feature is the most complained about feature in Word for the users I’ve worked with.

    It’s biggest problem is that it makes Word inconsistent and basic users hate that.

    Keep-It-Simple, turn off auto formatting and everyone gets a lot happier.

    Those that don’t understand advanced word processing features hate inconsistencies and hence they hate auto formatting.

    Advanced users also hate it and turn it off so that they can use the (then predicatable) advanced features.

    Don’t try and solve a problem that isn’t there. It would have been far better to provide easy to use ‘How do I?’ guides (which I’m pleased to see Office 2003 doing instead) to help people learn rather than try and second guess them. This is where MS can learn a lot from Apple I guess.

    It’s a clever solution none the less, it’s just that the coding effort would have been better spent elsewhere IMHO.


  3. Now if only something could be done about those who bang in hard returns at the end of every line within paragraphs. Take this as a right-margin-set intention? 😉

  4. Steven says:

    It is the first thing I disable because it really gets on my nerves. Can’t really blame the Word programmers because there’s no such thing as a MindReader(tm) input device (yet).

    Formatting in Word is one of my pet peeves, by the way. I get really annoyed when I see:

    – Paragraphs "indented" by holding down the space bar.

    – Crooked margins on said paragraphs.

    – Lots of useless spaces at the end of a line (which Word doesn’t do anything with).

    – Headings created by (often inconsistently) changing the font settings every time instead of just using the built-in paragraph styles.

    And I do see them because I always work with "Show all non-printing characters" enabled. Unfortunately, all these ignorant saps invariably send their documents to fix something that they can’t figure out… Eurgh.

  5. Jay Zipursky says:

    Interesting post. There is a similar problem with tabs inside tables. The default behavior is to switch focus to the next cell, but I just saw my wife hit this as she tried to insert a tab in Word 2003. The Ctrl-Tab solution is invisible and if I wasn’t there she may have damaged our computer in frustration. 🙂

    (Now, I suppose you could argue that tables are an "advanced" feature, but she was using an Avery label template which includes explicit instructions on its use.)

    Speaking of behaviours we don’t really want, could you write about how Word deals with numbered lists? (Maybe you have already?) This feature is an endless source of frustration for me. – Jay

  6. Marty CS says:

    Steve Hurcombe hits the nail on the head with his comments. I’ve been using computers and word processors for just shy of 20 years. I actually welcome learning how to do things the RIGHT way and use an application the way it was intended to be used, even if it requires a bit of a learning curve. Unfortunately Word in particular is a source of tremendous frustration for me because it is constantly second-guessing me. And sometimes, if I make a change (God forbid I decide to remove an extraneous return at the end of a paragraph, or worse a table), Word is horribly unpredictable, and sometimes the changes it forces on you are so sweeping it feels like there is no recovery. Even text selection can be a challenge. If I place the cursor on the second character of a word and drag, I want the starting point of my selection to be the second character of the word and beyond, not the whole freakin’ word… Sheesh! Generally speaking I type what I mean, and Word’s autocorrect, especially with regard to CAPITALIZATION is amazingly inaccurate in its attempt to mind-read my intentions. Turning all of that crap off is not EASY either. A good substitute that does less guessing, but will still reliably read/write MS Word docs, is hugely appealing to me. Pages, anyone??

  7. keith ray says:

    Now-a-days people are learning to type on word-processors… it’s hard to even FIND a typewriter… simulating type-writer behavior is almost as useless as simulating slide-rules.

  8. Jay Norris says:

    It has been said that disabling the auto-formatting feature is not easy. This is definitely true as it seems to exists in pieces, some of which are not apparently diableable.

    Is anyone aware of a registry patch to nuke this feature once and for good? I use Office XP(2002?).

  9. Olivier says:

    Jay: The Legend recounts that numerous people have searched for the Holy Patch To Nuke Auto Format Once And For All, but in their enthusiasm, tirelessly chasing the little bit that was left enabled, always ended up nuking their whole Office installation.

  10. Rick Schaut tries to explain why it was difficult to make Word’s Auto Formatter correctly guess what it should do, but his readers nailed the real reason: because the only certainty you have with something that acts differently each time…

  11. JMTee says:

    Cam anyone say where one could find a detailed list about all the auto-formatting features that should be turned off in Word? I don’t have the energy to go through all the preferences. I’m using Word 2004:mac.

  12. In the canonical Word weblog, we have The Case of the Missing Tab today. My goodness. No wonder I could never figure out exactly when Word would/would not insert a tab vs. indent the paragraphs….