View source for FreeHAL

{{Infobox software
| name                 = FreeHAL@home
| logo                 = FreeHAL_logo.png
| logo caption         = FreeHAL logo
| screenshot           = Freehal.png
| caption              = FreeHAL graphical interface
| description          = FreeHAL@home was a completed Artificial intelligence BOINC project that generated and converted semantic networks for the self-learning chatbot FreeHAL, developed by Tobias Schulz.
| status               = Completed
| category             = Artificial intelligence
| compute              = CPU
| dependencies         = None
| developer            = Tobias Schulz
| author               = Tobias Schulz
| sponsor              = CloudSigma (2010–2011); volunteer server donors including SETI.Germany and Planet 3DNow!
| maintainer           = Tobias Schulz
| released             = {{Start date and age|2008|09|26}}
| completed            = {{Start date and age|2012}}
| discontinued         = {{Start date and age|2013|04|07}}
| repository           = {{URL|https://github.com/freehal}}
| programming language = Java, Perl, C++, Python, PHP
| operating system     = Windows, Linux, Unix, BSD, macOS, Android
| size                 = ~6.8 MB (JEliza 2.2.2)
| stats as of          = {{Start date and age|2013|04|07}}
| average performance  = 12.24 TFLOPS (May 2012 peak reported)
| active users         = 0
| total users          = 18006
| active hosts         = 0
| total hosts          = 63407
| rac                  = 0
| credit per day       = 0
| gpu performance      = N/A (CPU only)
| cpu performance      = 12.24 TFLOPS (May 2012)
| website              = {{URL|https://freehal.github.io/}}
| license              = GPL-3.0-or-later
}}

'''FreeHAL@home''' (also written '''FreeHAL@Home''' or listed in statistics as '''FreeHAL''') was a completed [[BOINC]] volunteer computing project that generated and converted fact and relationship databases ([[semantic network]]s) for '''FreeHAL''', an open-source self-learning [[chatbot]].<ref name="wayback2011">{{cite web |title=FreeHAL@home |url=http://www.freehal.net/freehal_at_home/ |archive-url=https://web.archive.org/web/20110801052639/http://www.freehal.net/freehal_at_home |archive-date=1 August 2011 |website=freehal.net |access-date=24 August 2026}}</ref><ref name="enwiki">{{cite web |title=FreeHAL |url=https://en.wikipedia.org/wiki/FreeHAL |website=Wikipedia |access-date=24 August 2026}}</ref> The desktop program (originally named '''JEliza''') was written to imitate human conversation in German and English. After more than six years of mostly active development, the software project was discontinued in 2012; the BOINC servers last published statistics in April 2013 and never recovered from a database crash.<ref name="githubio">{{cite web |title=About FreeHAL |url=https://freehal.github.io/ |website=freehal.github.io |access-date=24 August 2026}}</ref><ref name="boincstats">{{cite web |title=FreeHAL - Detailed stats |url=https://www.boincstats.com/stats/78/project/detail |website=BOINCstats/BAM! |access-date=24 August 2026}}</ref>

== History ==

The program began around 2006 as '''JEliza'''. The name combined '''J'''ava, the first implementation language, with [[ELIZA]], Joseph Weizenbaum's 1966 conversation simulator.<ref name="linuxmag">{{cite magazine |last=Schnober |first=Carsten |title=Projects on the Move |magazine=Linux Magazine |issue=97 |date=December 2008 |pages=94–95 |url=https://web.archive.org/web/20120224065526/http://www.linux-magazine.com/w3/issue/97/094-095_projects.pdf |access-date=24 August 2026}}</ref><ref name="enwiki" /> Early releases (including Python, Perl, and Qt builds) were hosted at Gna!.<ref name="githubio" /> Heise listed JEliza 2.2.2 as a 6.77&nbsp;MB GNU-GPL download for Windows and Linux.<ref name="heise">{{cite web |title=JEliza 2.2.2 |url=http://freehal.github.io/mirrors/www.heise.de/download/jeliza-1155680.html |website=Heise (project mirror) |access-date=24 August 2026}}</ref>

In May 2008 the project was renamed '''FreeHAL''' after the language mix no longer matched the leading "J", and in homage to HAL 9000 from the film ''2001: A Space Odyssey''.<ref name="enwiki" /><ref name="dewiki">{{cite web |title=FreeHAL |url=https://de.wikipedia.org/wiki/FreeHAL |website=German Wikipedia |access-date=24 August 2026}}</ref> Lead developer [[Tobias Schulz]] remained the principal author, maintainer, and BOINC administrator throughout the project's life.<ref name="enwiki" /><ref name="wayback2011" />

[[BOINC]] first listed FreeHAL@home on 26 September 2008.<ref name="boincstats" /> Volunteers attached with the project URL <code>http://www.freehal.net/freehal_at_home/</code> (participants were warned to avoid the alternate host <code>boinc.freehal.org</code> during launch).<ref name="boincaf">{{cite web |title=Les sites des projets |url=https://www.boinc-af.org/les-sites-des-projets.html |website=BOINC-AF |access-date=24 August 2026}}</ref>

From August 2010 the Swiss cloud provider CloudSigma donated servers used for both the chatbot and the BOINC project. On 27 February 2011 Schulz announced that CloudSigma would continue that support for another twelve months; on 1 May 2011 he reported that CloudSigma would not extend the agreement. SETI.Germany and Planet 3DNow! members had also sponsored servers, and Elton Chung of ReactOS donated a download mirror.<ref name="wayback2011" /><ref name="freehalnet">{{cite web |title=FreeHAL@home |url=https://freehal.net/freehal_at_home |website=freehal.net |access-date=24 August 2026}}</ref>

The last numbered desktop release commonly cited is '''Step 6''' (8 April 2011).<ref name="enwiki" /> German Wikipedia records source revision 1447 dated 2 June 2012.<ref name="dewiki" /> An Android client appeared on Google Play in June 2012 (answers computed on remote servers). A Java port intended for Android and desktop was started in September 2012.<ref name="githubio" /> The official site later stated that after more than six years of mostly active development the project had been discontinued in 2012.<ref name="githubio" />

On 7 April 2013 a database server crash took FreeHAL@home offline. An offline notice said there was no way to access the project while recovery was attempted with the server donors.<ref name="wuprop">{{cite web |title=Freehal: Really? |url=https://wuprop.boinc-af.org/forum_thread.php?id=192 |website=WUProp@Home forums |date=12 June 2013 |access-date=24 August 2026}}</ref> BOINCstats last ingested user and team XML on 7 April 2013 and host XML on 6 April 2013.<ref name="boincstats" /> Combined-statistics maintainers later retired the listing after the servers had been offline for nearly a year.<ref name="netsoft">{{cite web |title=FreeHal@Home |url=https://boinc.netsoft-online.com/forum/suggestions/1016/freehalhome/ |website=BOINC Combined Statistics |access-date=24 August 2026}}</ref>

== Goals ==

The FreeHAL project's mission was to develop an open-source program that "very closely imitates human conversation."<ref name="wayback2011" /><ref name="githubio" /> FreeHAL@home existed so that large public semantic nets could be parsed and converted into the fact and relationship graphs used by that program. Those conversions were described as time-consuming and embarrassingly parallel, so they were packaged as BOINC workunits for volunteer hosts.<ref name="wayback2011" /><ref name="live2010">{{cite web |title=FreeHAL - free software artificial intelligence |url=https://freehal.net/freehal_at_home/index.php |website=freehal.net |access-date=24 August 2026}}</ref>

Unlike scripted commercial chatbots of the period, FreeHAL was advertised as learning on its own while talking to people over the keyboard, growing a knowledge database rather than only matching canned patterns.<ref name="enwiki" /><ref name="ars">{{cite web |title=FreeHAL@home |url=https://arstechnica.com/civis/viewtopic.php?f=18&t=37134 |website=Ars Technica OpenForum |date=January 2010 |access-date=24 August 2026}}</ref>

== Software architecture ==

FreeHAL was a client–server system. A server (called the '''kernel''' in project documentation) handled understanding and generation. Front ends included a cross-platform [[Qt (software)|Qt]] graphical user interface, a text client, a PHP web interface used on the project homepage, and later the Android app.<ref name="linuxmag" /><ref name="wayback2011" /> Several users could train one shared installation over the network.<ref name="linuxmag" />

Licensing was [[GNU General Public License|GNU GPL]] version 3 or later.<ref name="githubio" /> Supported operating systems included Microsoft Windows, GNU/Linux, Unix, BSD, and Mac OS X, with Android added in 2012.<ref name="enwiki" /><ref name="githubio" /> Implementation languages shifted over time from Java to Perl and then C++, with Python and PHP used for earlier and web components; a later Java port was begun in 2012.<ref name="linuxmag" /><ref name="dewiki" /><ref name="githubio" /> Knowledge was stored in an [[SQLite]] database.<ref name="linuxmag" /> Speech synthesis used MPlayer for playback and an online synthesizer operated by Schulz.<ref name="linuxmag" /> Source code, issue tracking, and later documentation live under the [https://github.com/freehal freehal] GitHub organization and Schulz's personal GitHub account.<ref name="githubio" />

== How conversation worked ==

From the computer's point of view a turn had three repeating stages: understand the human input, retrieve or infer an answer, and emit natural language.<ref name="linuxmag" /> The stack combined:

* a '''stemmer''' to reduce inflected forms to stems;
* a '''part-of-speech tagger''' to label grammatical roles;
* '''pattern recognition''' over the resulting tokens;
* '''part-of-speech databases''';
* a '''semantic network''' of facts and relations;
* [[Hidden Markov model]]s for statistical interpretation.<ref name="enwiki" /><ref name="linuxmag" />

A simple first-order HMM used for tagging or sequence interpretation can be written with hidden states <math>q_t</math>, observations <math>o_t</math>, transitions <math>a_{ij}</math>, and emissions <math>b_j(o)</math>:

<math>
P(q_1,\ldots,q_T,o_1,\ldots,o_T)
= P(q_1)\,b_{q_1}(o_1)
\prod_{t=2}^{T} a_{q_{t-1}q_t}\,b_{q_t}(o_t).
</math>

The Viterbi recurrence that recovers the most likely tag or dialog-state path is

<math>
V_t(j) = \max_i \bigl(V_{t-1}(i)\,a_{ij}\bigr)\,b_j(o_t).
</math>

Facts learned in conversation were stored as nodes and edges so the kernel could draw conclusions that had not been typed in as isolated sentences.<ref name="linuxmag" /> By late 2008 the public German demo already held more than 800,000 German terms and almost 200,000 relations, versus about 20,000 English words and 80,000 English relations; German remained the only language with a large semantic net.<ref name="linuxmag" /><ref name="dewiki" />

Linux Magazine noted typical limits of the era: confused word order, tense, number, and case; occasional infinite loops while learning that required wiping the database; and crashes, though day-to-day reliability was described as fairly good.<ref name="linuxmag" />

== FreeHAL@home on BOINC ==

Workunits converted open semantic-net dumps into FreeHAL's internal fact/relation format.<ref name="live2010" /> Because the application often used only a small fraction of one CPU (community reports put the useful work at a few seconds, then a long sleep so a unit lasted on the order of 90 minutes plus a random extra interval averaging about 10 minutes), it was commonly run '''alongside''' other BOINC projects. A relatively new BOINC Manager was required so non-CPU-intensive FreeHAL tasks could run concurrently with ordinary CPU work. Typical reported memory use was about 11–12&nbsp;MB per instance (ranging roughly 1–65&nbsp;MB). Community analysis of <code>hal2009-boinc.cpp</code> described a grant on the order of 12 credits per completed unit.<ref name="ars" /><ref name="berkeley">{{cite web |title=Thread 'Free Hal project.' |url=https://boinc.berkeley.edu/forum_thread.php?id=6761 |website=BOINC forums |date=24 July 2011 |access-date=24 August 2026}}</ref>

In June 2009 Schulz posted server messages explaining that simultaneous in-flight work had jumped from 10,000–30,000 units in May to almost 200,000, overwhelming the project server.<ref name="statsforum">{{cite web |title=Forum::The Projects::FreeHAL@home |url=https://www.boincstats.com/forum/10/4606 |website=BOINCstats |date=2009 |access-date=24 August 2026}}</ref> Monthly hosting was later said to cost about 80 currency units for bandwidth and traffic, and the project appealed for donations.<ref name="live2010" />

Applications were CPU-only. Platforms advertised over the project's life included Windows, Linux, and other Unix-like systems used by the chatbot itself.<ref name="enwiki" />

== Project statistics ==

[[File:parsetree.png|thumb|Example FreeHAL parse tree from the official project site|400x400px]]

BOINCstats classifies the project under Artificial intelligence and records these lifetime figures after the final XML export of April 2013:<ref name="boincstats" />

{| class="wikitable"
! Metric !! Value
|-
| First seen || 26 September 2008
|-
| Total credit || 3,680,102,220
|-
| Users (all time) || 18,006
|-
| Hosts (all time) || 63,407
|-
| Teams || 798
|-
| Active users / hosts (today) || 0 / 0
|-
| RAC || 0
|-
| Contribution to combined BOINC credit || about 0.0077%
|}

A May 2012 snapshot (while the project was still granting credit) listed about 14,600 users (2,763 active), 52,331 hosts (6,878 active), 680 teams, RAC of 2,448,500, and about 12.24&nbsp;TFLOPS of equivalent throughput.<ref name="boincstats2012">{{cite web |title=BOINCstats FreeHAL graph |url=https://web.archive.org/web/20120501220035/http://boincstats.com/stats/project_graph.php?pr=freehal |archive-url=https://web.archive.org/web/20120501220035/http://boincstats.com/stats/project_graph.php?pr=freehal |archive-date=1 May 2012 |website=BOINCstats |access-date=24 August 2026}}</ref>

== Awards and reception ==

In 2008 FreeHAL won first prize in the '''Most Popular''' category of the international [[Chatterbox Challenge]].<ref name="enwiki" /><ref name="cbc">{{cite web |title=The Chatterbox Challenge |url=http://www.daniellechuchran.com/contest_history.html |archive-url=https://web.archive.org/web/20100924042534/http://www.daniellechuchran.com/contest_history.html |archive-date=24 September 2010 |access-date=24 August 2026}}</ref>

As JEliza it appeared on the cover CD/DVD of the German magazine ''com! Das Computer-Magazin'' in issues 4/2008 and 5/2008 and was listed among that month's Top-10 open-source programs.<ref name="dewiki" /><ref name="com4">{{cite web |title=Top-10 des Monats |url=http://www.com-magazin.de/hefte/artikelarchiv/com-artikel/top-10-des-monats-8.html |website=com! |access-date=24 August 2026}}</ref> ''Linux Magazine'' issue 97 (December 2008) devoted a projects column to FreeHAL, placing it in the lineage of the [[Turing test]] and describing stemmers, taggers, HMMs, SQLite storage, and the BOINC subproject.<ref name="linuxmag" /> LinuxCommunity likewise highlighted the 2008 Chatterbox win and the research aim of simulating linguistic intelligence.<ref name="linuxcomm">{{cite web |title=FreeHAL - Die neue Gattung maschineller Intelligenz |url=https://www.linux-community.de/nachrichten/FreeHAL-Die-neue-Gattung-maschineller-Intelligenz/ |website=LinuxCommunity |date=1 September 2008 |access-date=24 August 2026}}</ref>

Volunteer forums (Ars Technica, BOINC, SETI.Germany, Planet 3DNow!) treated FreeHAL@home as a light "sidecar" project. Some crunchers liked the credit-to-CPU ratio; others questioned whether the sleep-padded workunits did useful science.<ref name="ars" />

== Publications ==

No peer-reviewed paper authored by the FreeHAL team was located in major indexes. Contemporary and later publications that discuss the program include:

* Carsten Schnober, "Projects on the Move," ''Linux Magazine'' 97 (December 2008), pp. 94–95. Feature on FreeHAL's NLP pipeline, knowledge sizes, client–server design, and FreeHAL@home.<ref name="linuxmag" />
* ''com! Das Computer-Magazin'', issues 4/2008 and 5/2008: JEliza on the magazine disc and in the monthly Top-10 open-source list.<ref name="dewiki" />
* Mikic, Burguillo, Peleteiro, and Rey-López, "Using Tags In An AIML-based Chatterbot To Improve Its Knowledge," ''Computer Science'' 13 (2) 2012, pp. 123 ff. Cited in the German Wikipedia literature list for FreeHAL.<ref name="dewiki" />
* English and German [[Wikipedia]] articles, and the DBpedia extraction of the English article.<ref name="enwiki" /><ref name="dbpedia">{{cite web |title=About: FreeHAL |url=https://dbpedia.org/page/FreeHAL |website=DBpedia |access-date=24 August 2026}}</ref>

== Legacy ==

Code, old Gna! homepage mirrors, 2008 screenshots (Ubuntu 7.04 and OS X 10.4.10), and historical downloads remain on [https://freehal.github.io/ freehal.github.io].<ref name="githubio" /> The BOINC attach URL and live servers are gone. Lifetime credit and host counts are preserved at [[BOINCstats]].<ref name="boincstats" /> FreeHAL is still listed among historical volunteer-computing and chatbot projects on Wikipedia's lists of AI and BOINC-related software.<ref name="enwiki" />

== See also ==

* [[BOINC projects]]
* [[Main Page]]
* [[Axiom Distributed AI]]
* [[MindModeling@Home]]
* [[MLC@Home]]
* [[Chess@Home]]
* [[Yoyo@home]]
* [[WUProp@Home]]
* [[BOINC Central]]
* [[BOINC Alpha Test]]
* [[SciLINC]]

== External links ==

* [https://freehal.github.io/ Official archival site]
* [https://github.com/freehal Source repositories]
* [https://web.archive.org/web/20110801052639/http://www.freehal.net/freehal_at_home/ Wayback Machine: FreeHAL@home (1 August 2011)]
* [https://www.boincstats.com/stats/78/project/detail BOINCstats project page]
* [https://en.wikipedia.org/wiki/FreeHAL English Wikipedia]
* [https://de.wikipedia.org/wiki/FreeHAL German Wikipedia]
* [https://web.archive.org/web/20120224065526/http://www.linux-magazine.com/w3/issue/97/094-095_projects.pdf Linux Magazine 97 PDF (archive)]

== References ==

{{Reflist}}

[[Category:Completed BOINC projects]]
[[Category:Artificial intelligence]]
[[Category:Chatbots]]
[[Category:Volunteer computing projects]]
[[Category:Free software]]
[[Category:Software using the GPL license]]