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78 >1. General Information</H1
86 >1.1. Who should use Privoxy?</H3
88 > Anyone that is interested in security, privacy, or in
89 finer-grained control over their web and Internet experience.
90 Everyone is encouraged to try <SPAN
103 >1.2. Is Privoxy the best choice for
109 > is certainly a good choice, especially for those who want more
110 control and security. Those that have the ability to fine-tune their installation
111 will benefit the most. One of <SPAN
115 strength's is that it is highly configurable giving you the ability to
116 completely personalize your installation. Being familiar with, or at least
117 having an interest in learning about <A
118 HREF="http://en.wikipedia.org/wiki/Http"
121 > and other networking
123 HREF="http://en.wikipedia.org/wiki/Html"
128 HREF="http://en.wikipedia.org/wiki/Internet_Protocol"
134 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
142 will be a big plus and will help you get the most out of <SPAN
146 A new installation just includes a very basic configuration. The user
147 should take this as a starting point only, and enhance it as he or she
148 sees fit. In fact, the user is encouraged, and expected to, fine-tune the
155 > configuration can be done
157 HREF="http://en.wikipedia.org/wiki/Web_browser"
161 But there are areas where configuration is done using a
163 HREF="http://en.wikipedia.org/wiki/Text_editors"
167 to edit configuration files.
177 >1.3. What is a <SPAN
184 HREF="http://en.wikipedia.org/wiki/Proxy_server"
188 is a service, based on a software such as
192 >, that clients (i.e. browsers) can use
193 instead of connecting directly to web servers on the Internet. The
194 clients then ask the proxy to fetch the objects they need (web pages,
195 images, movies etc) on their behalf, and when the proxy has done so, it
196 hands the results back to the client. It is a <SPAN
201 HREF="http://en.wikipedia.org/wiki/Proxy_server"
208 > There are many reasons to use web proxies, such as security (firewalling),
209 efficiency (caching) and others, and there are any number of proxies
210 to accommodate those needs.
216 > is a proxy that is primarily focused on privacy
217 protection, ad and junk elimination and freeing the user from restrictions placed on his
218 activities. Sitting between your browser(s) and the Internet,
219 it is in a perfect position to filter outbound personal information that your
220 browser is leaking, as well as inbound junk. It uses a variety of techniques to do
221 this, all of which are under your complete control via the various configuration
232 >1.4. What is this new version of
238 > A long time ago, there was the
240 HREF="http://www.junkbusters.com/ijb.html"
244 >Internet Junkbuster</SPAN
247 by Anonymous Coders and <A
248 HREF="http://www.junkbusters.com/"
252 >. This saved many users a lot of pain in the early days of
253 web advertising and user tracking.</P
255 > But the web, its protocols and standards, and with it, the techniques for
256 forcing ads on users, give up autonomy over their browsing, and
257 for tracking them, keeps evolving. Unfortunately, the <SPAN
261 > did not. Version 2.0.2, published in 1998, was
262 (and is) the last official
264 HREF="http://www.junkbusters.com/ijbdist.html#release"
269 HREF="http://www.junkbusters.com"
271 >Junkbusters Corporation</A
273 Fortunately, it had been released under the GNU
275 HREF="http://www.gnu.org/licenses/gpl.html"
278 >, which allowed further
279 development by others.</P
281 > So Stefan Waldherr started maintaining an
283 HREF="http://www.waldherr.org/junkbuster/"
285 >improved version of the
287 >, to which eventually a number of people contributed patches.
288 It could already replace banners with a transparent image, and had a first
289 version of pop-up killing, but it was still very closely based on the
290 original, with all its limitations, such as the lack of HTTP/1.1 support,
291 flexible per-site configuration, or content modification. The last release
292 from this effort was version 2.0.2-10, published in 2000.</P
296 HREF="http://www.privoxy.org/user-manual/copyright.html#AUTHORS"
300 picked up the thread, and started turning the software inside out, upside down,
301 and then reassembled it, adding many
303 HREF="http://www.privoxy.org/user-manual/introduction.html#FEATURES"
309 > The result of this is <SPAN
313 stable version, 3.0, was released August, 2002.
326 >? Why change the name from
327 Junkbuster at all?</H3
330 HREF="http://junkbusters.com/"
332 >Junkbusters Corporation</A
334 continues to offer their original version of the <SPAN
342 >-derived software under the same name
345 > There are also potential legal complications from the continued use of the
349 > name, which is a registered trademark of
351 HREF="http://junkbusters.com/"
353 >Junkbusters Corporation</A
355 There are, however, no objections from Junkbusters Corporation to the
359 > project itself, and they, in fact, still
360 share our ideals and goals.</P
362 > The developers also believed that there are so many improvements over the original
363 code, that it was time to make a clean break from the past and make
364 a name in their own right.</P
376 >Privacy Enhancing Proxy</I
380 modification and junk suppression gives <SPAN
387 control, more freedom, and allows you to browse your personal and
406 >1.6. How does Privoxy differ
407 from the old Junkbuster?</H3
416 > left off. All the old features remain.
420 > still blocks ads and banners,
422 HREF="http://en.wikipedia.org/wiki/Browser_cookie"
426 helps protect your privacy. But, these are all greatly enhanced, and many,
427 many new features have been added, all in the same vein.
430 > The configuration has changed significantly as well. This is something that
431 users will notice right off the bat if upgrading from
445 > and much more has been
446 combined into the <SPAN
449 > files, with a completely different
451 HREF="../user-manual/whatsnew.html"
455 page for the latest updates.</P
460 >'s new features include:</P
467 > Integrated browser based configuration and control utility at <A
468 HREF="http://config.privoxy.org/"
470 >http://config.privoxy.org/</A
477 tracing of rule and filter effects. Remote toggling.
482 > Web page content filtering (removes banners based on size,
486 >, JavaScript and HTML annoyances, pop-up windows, etc.)
491 > Modularized configuration that allows for standard settings and
492 user settings to reside in separate files, so that installing updated
493 actions files won't overwrite individual user settings.
498 > HTTP/1.1 compliant (but not all optional 1.1 features are supported).
503 > Support for Perl Compatible Regular Expressions in the configuration files, and
504 generally a more sophisticated and flexible configuration syntax over
510 > Improved cookie management features (e.g. session based cookies).
520 > Bypass many click-tracking scripts (avoids script redirection).
525 > Multi-threaded (POSIX and native threads).
530 > User-customizable HTML templates for all proxy-generated pages (e.g. "blocked" page).
535 > Auto-detection and re-reading of config file changes.
540 > Improved signal handling, and a true daemon mode (Unix).
545 > Every feature now controllable on a per-site or per-location basis, configuration
546 more powerful and versatile over-all.
551 > Many smaller new features added, limitations and bugs removed, and security holes fixed.
564 >1.7. How does Privoxy know what is
565 an ad, and what is not?</H3
570 >'s approach to blocking ads is twofold:</P
572 > First, there are certain patterns in the <SPAN
579 of banner images. This applies to both the path (you wouldn't guess how many
580 web sites serve their banners from a directory called <SPAN
584 and the host (blocking the big banner hosting services like doublecklick.net
585 already helps a lot). <SPAN
588 > takes advantage of this
590 HREF="../user-manual/actions-file.html#AF-PATTERNS"
594 > to sort out and block the requests for things that sound
595 like they would be ads or banners.</P
597 > Second, banners tend to come in certain <SPAN
604 can't tell the size of an image by its URL without downloading it, and if you
605 do, it's too late to save bandwidth. Therefore, <SPAN
609 also inspects the HTML sources of web pages while they are loaded, and replaces
610 references to images with standard banner sizes by dummy references, so that
611 your browser doesn't request them anymore in the first place.</P
613 > Both of this involves a certain amount of guesswork and is, of course, freely
614 and readily configurable.</P
623 >1.8. Can Privoxy make mistakes?
624 This does not sound very scientific.</H3
626 > Actually, it's a black art ;-) And yes, it is always possible to have a broad
627 rule accidentally block or change something by mistake. You will almost surely
628 run into such situations at some point. It is tricky writing rules to
629 cover every conceivable possibility, and not occasionally get false positives.</P
631 > But this should not be a big concern since the
635 > configuration is very flexible, and
636 includes tools to help identify these types of situations so they can be
637 addressed as needed, allowing you to customize your installation.
639 HREF="trouble.html#BADSITE"
640 >See the Troubleshooting section below</A
650 >1.9. Will I have to configure Privoxy
651 before I can use it?</H3
653 > No, not really. The default installation should give you a good starting
654 point, and block <SPAN
660 > unwanted content.</P
662 > But you will certainly run into situations where there are false positives,
663 or ads not being blocked that you may not want to see. In these cases, you
664 would certainly benefit by customizing <SPAN
668 configuration to more closely match your individual situation. And we would
669 encourage you to do this. This is where the real power of
675 > You will have to tell your browser about <SPAN
679 (see the Installation section below).</P
688 >1.10. My browser does the same things as
689 Privoxy. Why should I use
692 > Modern browsers do indeed have <SPAN
699 functionality as <SPAN
703 adequate for you. But <SPAN
707 versatile and powerful, and can do a number of things that browsers just can't.
710 > In addition, a proxy is good choice if you use multiple browsers, or
711 have a LAN with multiple computers. This way all the configuration
712 is in one place, and you don't have to maintain a similar configuration
713 for possibly many browsers.
723 >1.11. Why should I trust Privoxy?</H3
725 > The most important reason is because you have access to
732 >, and you can control everything. You can
733 check every line of every configuration file yourself. You can check every
734 last bit of source code should you desire. And even if you can't read code,
735 there should be some comfort in knowing that thousands of other people can,
736 and do read it. You can build the software from scratch, if you want, so
737 that you know the executable is clean, and that it is
744 >. In fact, we encourage this level of scrutiny. It
745 is one reason we use <SPAN
758 >1.12. Is there is a license or fee? What about a
759 warranty? Registration?</H3
764 > is licensed under the <A
765 HREF="http://www.gnu.org/copyleft/gpl.html"
767 >GNU General Public License (GPL)</A
769 It is free to use, copy, modify or distribute as you wish under the terms of this
770 license. Please see the <A
771 HREF="copyright.html"
774 information on the license and copyright. Or the <TT
778 that should be included.
787 > of any kind, expressed, implied or otherwise.
788 That is something that would cost real money ;-) There is no registration either.
809 >1.13. Can Privoxy remove spyware? Adware? Viruses?</H3
814 > cannot remove anything. It is not a removal tool. It is a
818 > can help prevent contact from sites
819 that use such tactics with approriate configuration rules, and thus could
820 conceivably prevent contamination from such sites.</P
829 >1.14. Can I use Privoxy with other ad-blocking software?</H3
834 > should work fine with other proxies and other software in general.</P
836 > But it is probably not necessary to use <SPAN
839 > in conjunction with other
840 ad-blocking products, and this could conceivably cause undesirable results.
841 It would be better to choose one software or the other and work a little to
842 tweak its configuration to your liking.</P
851 >1.15. I would like to help you, what can I do?</H3
859 >1.15.1. Would you like to participate?</H4
867 > need help. There is something for
868 everybody who wants to help us. We welcome new developers, packagers,
869 testers, documentation writers or really anyone with a desire to help in
880 >. There are many other tasks available. In fact,
881 the programmers often can't spend as much time programming because of some
882 of the other, more mundane things that need to be done, like checking the
883 Tracker feedback sections.
887 HREF="https://sourceforge.net/account/register.php"
889 >get an account on SourceForge.net</A
891 and mail your id to the <A
892 HREF="mailto:ijbswa-developers@lists.sourceforge.net"
896 >. Then, please read the <A
897 HREF="../developer-manual/index.html"
899 >Developer's Manual</A
901 the pertinent sections.</P
903 > Once we have added you to the team, you'll have access to the <A
904 HREF="http://sourceforge.net/cvs/?group_id=11118"
908 together we'll find a suitable task for you.</P
915 NAME="JOINTEAM-MONEY"
917 >1.15.2. Contribute!</H4
919 > We, of course, welcome donations and could use money for domain registering,
920 buying software to test <SPAN
923 > with, and, of course,
924 for regular world-wide get-togethers (hahaha). If you enjoy the software and feel
925 like helping us with a donation, just <A
926 HREF="mailto: ijbswa-developers@lists.sourceforge.net"
936 NAME="JOINTEAM-SOFTWARE"
938 >1.15.3. Software</H4
940 > If you are a vendor of a web-related software like a browser, web server
941 or proxy, and would like us to ensure that <SPAN
945 runs smoothly with your product, you might consider supplying us with a
946 copy or license. We can't, however, guarantee that we will fix all potential
947 compatibility issues as a result.</P
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