Does interface research indicate Arial is better than Verdana/Tahoma (for on screen reading)
I know Google does A LOT of user interface/experience testing and I'm looking for any type of scientific research on User Experience when it comes to typefaces used on a monitor display.
As such, I'm going to use Google as an example.
Why doesn't Google use the typeface of Verdana or Tahoma (instead of helvetica/arial)?
Verdana/Tahoma were both typefaces primarily designed for the screen (and are much easier to read on the screen than helvetica/arial).
I'm curious to know if there is any type of computer science research indicating that Helvetica / Arial on the screen is better to use than other typefaces.
**Please note this is a computer science interaction research question instead of just a subjective web development question.
UPDATE:
People have been mentioning in the answers that Verdana/Tahoma are typically not available on Linux. But that answer doesn't make sense because CSS allows for this exact situation (of non-available fonts through the use of hierarchical typeface naming).
For example, in CSS you'd do
font-family:Verdana, sans-serif;
meaning - if the user has "verdana" us it, otherwise default to the system sans-serif typeface.
UPDATE 2
Google is already font stacking on the front page of Google.com using a Windows only font.
Per the CSS on google.com, they have:
font-family:arial,sans-serif
So all of the answers related to google not using certain fonts because of licensing issues, or not available on non-Windows machines, or filesize of the page are all wrong. Obviously, from the pasted code above, Google is explicitly defining a Windows only font (Arial) in such a way that increases the overall page size.
As such, my original question still stand: is any type of computer science research indicating that Helvetica / Arial on the screen is better to use than other typefaces.
**Please note this is a computer science interaction research question instead of just a subjective web development question.
Answer
I am assuming your question is about general studies comparing Arial to Tahoma/Verdana.
Let me state beforehand that any kind of "better" is highly subjective, but yet there are studies trying to do the impossible.
The first study I want to show you comparing Arial to Tahoma/Verdana shows that from the surveyed people Arial was the most preferred font, with Verdana coming in at second place and Tahoma third (out of the three). However that Arial was the preferred choice might be due to the study at hand as the researches indicate:
[...] since it has been most preferred in our previous font studies that examined children (Bernard, Mills, Frank, & McKown, Winter/2001), older adults (Bernard, Liao, & Mills, Winter/2001), and college students (Bernard & Mills, Summer/2000)
from A Comparison of Popular Online Fonts: Which is Best and When?
Interestingly the study was conducted on a computer, so even though Verdana was designed for the screen the participants still chose Arial over Verdana - maybe because people are so accustomed to seeing Arial/Helvetica everywhere?
A newer study (2002 compared to the last study from 2001) suggests that Verdana is the best choice:
Of the fonts studied, Verdana appears to be the best overall font choice. Besides being the most preferred, it was read fairly quickly and was perceived as being legible.
from A Comparison of Popular Online Fonts: Which Size and Type is Best?
Yet another study would classify Verdana as "dull", Arial as "unimaginative, stable, conformist" which you can read all about here: Perception of Fonts: Perceived Personality Traits and Uses.
If you are looking for results for only elderly people, Arial is the way go at 14 point size, but at 12 point size Verdana wins: Determining the Best Online Font for Older Adults.
A even more recent study (2007) investigating the "Psychology of onscreen type: investigations regarding typeface personality, appropriateness, and impact on document perception" (btw that is 652 pages of font goodness!) shows that Verdana has the highest legibility ranking of all fonts, the same study also finds that 21 people voted Verdana as their favorite, but 60 voted for Arial (again maybe because they KNOW the look of Arial?).
If anything I would suggest you read the last mentioned 652-page study. As for your question why Google chose Arial over Verdana - I don't know. Verdana was designed for the screen using hinting to snap the stems to pixels - hence it looks clearer on screen. People are accustomed to seeing Arial everywhere though, so they might get a feeling of "being at home".
If you want to open another can of worms, look into serif vs sans-serif fonts. Serif fonts are more legible in print, but on the web sans-serif fonts predominate - several studies exist comparing these findings.