Thanks for your replies. You have helped to dispel the wrong impressions that I had, namely:
1. That using a portable browser in a usb thumb drive would avoid/reduce the risk of virus infestation to my host computers. From jdhurst I gather that virus cannot be contracted from surfing the internet (respectable websites, of course). Then, does it mean that virus infest only through emails? I only use the portable browser on my two laptops, and so there is no risk of spreading or getting virus from other peoples' computers.
2. That using a portable browser would not leave traces on the host computers. I only surf on my own computers and never on other peoples'. But the reason I use the usb is to avoid getting "memory" traces/junk all over my computers, as I gather from the following two blurps:
http://www.adata.com.tw/adata_en/produc ... ductNo=138
http://portableapps.com/about/what_is_a_portable_app
Below is a quote/paste but it seems like the nytimes URL has lately been disabled; anyway, you may be interested in the writeup for whatever it's worth:
http://www.nytimes.com/2005/11/28/opinion/28mon4.html
Editorial Observer
What Google Should Roll Out Next: A Privacy Upgrade
By ADAM COHEN
Published: November 28, 2005
At a North Carolina strangulation-murder trial this month, prosecutors
announced an unusual piece of evidence: Google searches allegedly done
by the defendant that included the words "neck" and "snap." The data
were taken from the defendant's computer, prosecutors say. But it might
have come directly from Google, which - unbeknownst to many users -
keeps records of every search on its site, in ways that can be traced
back to individuals.
Google is rolling out revolutionary new features at a blistering rate,
most recently Google Base, which could evolve into a classified ad
service, and the Google Book Search Library Project, which aims to put
a vast number of books online. Google's stock recently soared past $400
a share, putting its market capitalization ahead of Time Warner and
Gannett combined, and the personal fortunes of its founders, Sergey
Brin and Larry Page, above $14 billion.
Google is the subject of a new book, "The Google Story," by David Vise
and Mark Malseed, that tracks the company's rise from a student project
at Stanford through its success in outmaneuvering Microsoft, Yahoo, AOL
and other behemoths for Internet dominance. Google has long presented
itself as the anti-Microsoft, a company that the digerati regard as a
force for good in the technology world.
In many ways, it has lived up to that reputation. But if it wants to
hold on to its corporate halo, Google should do a better job of
including users in decisions about how their personal information is
collected, stored, and shared.
Google has succeeded so extraordinarily because its founders were able
to see the future of the Internet more clearly than the rest of Silicon
Valley. At a time when "Web portals" - sites that directed users to
online services - were seen as the future, Mr. Brin and Mr. Page were
convinced Internet searches would be pivotal. They developed technology
that was far better than other search engines at sifting through the
galaxy of information online. They slapped a typo of a name on their
project - a misspelling of "googol," the number represented by a 1
followed by 100 zeroes - got venture capital, and quickly built a
company.
Mr. Brin and Mr. Page believed companies should not be able to get
better placement on the results page by paying money, something their
competitors allowed. Google strictly separated out "sponsored" results,
or ads, from search results, and gave up untold millions of dollars in
revenue by keeping Google's home page ad free. The company has taken
other idealistic positions over its short lifetime, including
conducting its initial public offering by a "Dutch auction," so Wall
Street would not control it.
Google operates according to two core principles. One is its mission
"to organize the world's information and make it universally accessible
and useful." The other is its motto, "Don't be evil," which Mr. Brin
and Mr. Page take so seriously that they included it in a Securities
and Exchange Commission filing. As Google grows and spreads into new
areas, these two principles are turning out to be in tension. Google's
book search, for example, aims to make books universally accessible in
a way some authors regard as dismissive of their rights and illegal.
The biggest area where Google's principles are likely to conflict is
privacy. Google has been aggressive about collecting information about
its users' activities online. It stores their search data, possibly
forever, and puts "cookies" on their computers that make it possible to
track those searches in a personally identifiable way - cookies that do
not expire until 2038. Its e-mail system, Gmail, scans the content of
e-mail messages so relevant ads can be posted. Google's written privacy
policy reserves the right to pool what it learns about users from their
searches with what it learns from their e-mail messages, though Google
says it won't do so. It also warns that users' personal information may
be processed on computers located in other countries.
The government can gain access to Google's data storehouse simply by
presenting a valid warrant or subpoena. Under the Patriot Act, Google
may not be able to tell users when it hands over their searches or
e-mail messages. If the federal government announced plans to directly
collect the sort of data Google does, there would be an uproar - in
fact there was in 2003, when the Pentagon announced its Total
Information Awareness program, which was quickly shut down.
In the early days of the Internet, privacy advocates argued that data
should be collected on individuals only if they affirmatively agreed.
But businesses like Google have largely succeeded in reversing the
presumption. There is a privacy policy on the site, but many people
don't read privacy policies. It is hard to believe most Google users
know they have a cookie that expires in 2038, or have thought much
about the government's ability to read their search history and stored
e-mail messages without them knowing it.
Google says it needs the data it keeps to improve its technology, but
it is doubtful it needs so much personally identifiable information. Of
course, this sort of data is enormously valuable for marketing. The
whole idea of "Don't be evil," though, is resisting lucrative business
opportunities when they are wrong. Google should develop an overarching
privacy theory that is as bold as its mission to make the world's
information accessible - one that can become a model for the online
world. Google is not necessarily worse than other Internet companies
when it comes to privacy. But it should be doing better.
end of quote/paste
