1 2 GNU Free Documentation License 3 Version 1.3, 3 November 2008 4 5 6 Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. 7 <http://fsf.org/> 8 Everyone is permitted to copy and distribute verbatim copies 9 of this license document, but changing it is not allowed. 10 11 0. PREAMBLE 12 13 The purpose of this License is to make a manual, textbook, or other 14 functional and useful document "free" in the sense of freedom: to 15 assure everyone the effective freedom to copy and redistribute it, 16 with or without modifying it, either commercially or noncommercially. 17 Secondarily, this License preserves for the author and publisher a way 18 to get credit for their work, while not being considered responsible 19 for modifications made by others. 20 21 This License is a kind of "copyleft", which means that derivative 22 works of the document must themselves be free in the same sense. It 23 complements the GNU General Public License, which is a copyleft 24 license designed for free software. 25 26 We have designed this License in order to use it for manuals for free 27 software, because free software needs free documentation: a free 28 program should come with manuals providing the same freedoms that the 29 software does. But this License is not limited to software manuals; 30 it can be used for any textual work, regardless of subject matter or 31 whether it is published as a printed book. We recommend this License 32 principally for works whose purpose is instruction or reference. 33 34 35 1. APPLICABILITY AND DEFINITIONS 36 37 This License applies to any manual or other work, in any medium, that 38 contains a notice placed by the copyright holder saying it can be 39 distributed under the terms of this License. Such a notice grants a 40 world-wide, royalty-free license, unlimited in duration, to use that 41 work under the conditions stated herein. The "Document", below, 42 refers to any such manual or work. Any member of the public is a 43 licensee, and is addressed as "you". You accept the license if you 44 copy, modify or distribute the work in a way requiring permission 45 under copyright law. 46 47 A "Modified Version" of the Document means any work containing the 48 Document or a portion of it, either copied verbatim, or with 49 modifications and/or translated into another language. 50 51 A "Secondary Section" is a named appendix or a front-matter section of 52 the Document that deals exclusively with the relationship of the 53 publishers or authors of the Document to the Document's overall 54 subject (or to related matters) and contains nothing that could fall 55 directly within that overall subject. (Thus, if the Document is in 56 part a textbook of mathematics, a Secondary Section may not explain 57 any mathematics.) The relationship could be a matter of historical 58 connection with the subject or with related matters, or of legal, 59 commercial, philosophical, ethical or political position regarding 60 them. 61 62 The "Invariant Sections" are certain Secondary Sections whose titles 63 are designated, as being those of Invariant Sections, in the notice 64 that says that the Document is released under this License. If a 65 section does not fit the above definition of Secondary then it is not 66 allowed to be designated as Invariant. The Document may contain zero 67 Invariant Sections. If the Document does not identify any Invariant 68 Sections then there are none. 69 70 The "Cover Texts" are certain short passages of text that are listed, 71 as Front-Cover Texts or Back-Cover Texts, in the notice that says that 72 the Document is released under this License. A Front-Cover Text may 73 be at most 5 words, and a Back-Cover Text may be at most 25 words. 74 75 A "Transparent" copy of the Document means a machine-readable copy, 76 represented in a format whose specification is available to the 77 general public, that is suitable for revising the document 78 straightforwardly with generic text editors or (for images composed of 79 pixels) generic paint programs or (for drawings) some widely available 80 drawing editor, and that is suitable for input to text formatters or 81 for automatic translation to a variety of formats suitable for input 82 to text formatters. A copy made in an otherwise Transparent file 83 format whose markup, or absence of markup, has been arranged to thwart 84 or discourage subsequent modification by readers is not Transparent. 85 An image format is not Transparent if used for any substantial amount 86 of text. A copy that is not "Transparent" is called "Opaque". 87 88 Examples of suitable formats for Transparent copies include plain 89 ASCII without markup, Texinfo input format, LaTeX input format, SGML 90 or XML using a publicly available DTD, and standard-conforming simple 91 HTML, PostScript or PDF designed for human modification. Examples of 92 transparent image formats include PNG, XCF and JPG. Opaque formats 93 include proprietary formats that can be read and edited only by 94 proprietary word processors, SGML or XML for which the DTD and/or 95 processing tools are not generally available, and the 96 machine-generated HTML, PostScript or PDF produced by some word 97 processors for output purposes only. 98 99 The "Title Page" means, for a printed book, the title page itself, 100 plus such following pages as are needed to hold, legibly, the material 101 this License requires to appear in the title page. For works in 102 formats which do not have any title page as such, "Title Page" means 103 the text near the most prominent appearance of the work's title, 104 preceding the beginning of the body of the text. 105 106 The "publisher" means any person or entity that distributes copies of 107 the Document to the public. 108 109 A section "Entitled XYZ" means a named subunit of the Document whose 110 title either is precisely XYZ or contains XYZ in parentheses following 111 text that translates XYZ in another language. (Here XYZ stands for a 112 specific section name mentioned below, such as "Acknowledgements", 113 "Dedications", "Endorsements", or "History".) To "Preserve the Title" 114 of such a section when you modify the Document means that it remains a 115 section "Entitled XYZ" according to this definition. 116 117 The Document may include Warranty Disclaimers next to the notice which 118 states that this License applies to the Document. These Warranty 119 Disclaimers are considered to be included by reference in this 120 License, but only as regards disclaiming warranties: any other 121 implication that these Warranty Disclaimers may have is void and has 122 no effect on the meaning of this License. 123 124 2. VERBATIM COPYING 125 126 You may copy and distribute the Document in any medium, either 127 commercially or noncommercially, provided that this License, the 128 copyright notices, and the license notice saying this License applies 129 to the Document are reproduced in all copies, and that you add no 130 other conditions whatsoever to those of this License. You may not use 131 technical measures to obstruct or control the reading or further 132 copying of the copies you make or distribute. However, you may accept 133 compensation in exchange for copies. If you distribute a large enough 134 number of copies you must also follow the conditions in section 3. 135 136 You may also lend copies, under the same conditions stated above, and 137 you may publicly display copies. 138 139 140 3. COPYING IN QUANTITY 141 142 If you publish printed copies (or copies in media that commonly have 143 printed covers) of the Document, numbering more than 100, and the 144 Document's license notice requires Cover Texts, you must enclose the 145 copies in covers that carry, clearly and legibly, all these Cover 146 Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on 147 the back cover. Both covers must also clearly and legibly identify 148 you as the publisher of these copies. The front cover must present 149 the full title with all words of the title equally prominent and 150 visible. You may add other material on the covers in addition. 151 Copying with changes limited to the covers, as long as they preserve 152 the title of the Document and satisfy these conditions, can be treated 153 as verbatim copying in other respects. 154 155 If the required texts for either cover are too voluminous to fit 156 legibly, you should put the first ones listed (as many as fit 157 reasonably) on the actual cover, and continue the rest onto adjacent 158 pages. 159 160 If you publish or distribute Opaque copies of the Document numbering 161 more than 100, you must either include a machine-readable Transparent 162 copy along with each Opaque copy, or state in or with each Opaque copy 163 a computer-network location from which the general network-using 164 public has access to download using public-standard network protocols 165 a complete Transparent copy of the Document, free of added material. 166 If you use the latter option, you must take reasonably prudent steps, 167 when you begin distribution of Opaque copies in quantity, to ensure 168 that this Transparent copy will remain thus accessible at the stated 169 location until at least one year after the last time you distribute an 170 Opaque copy (directly or through your agents or retailers) of that 171 edition to the public. 172 173 It is requested, but not required, that you contact the authors of the 174 Document well before redistributing any large number of copies, to 175 give them a chance to provide you with an updated version of the 176 Document. 177 178 179 4. MODIFICATIONS 180 181 You may copy and distribute a Modified Version of the Document under 182 the conditions of sections 2 and 3 above, provided that you release 183 the Modified Version under precisely this License, with the Modified 184 Version filling the role of the Document, thus licensing distribution 185 and modification of the Modified Version to whoever possesses a copy 186 of it. In addition, you must do these things in the Modified Version: 187 188 A. Use in the Title Page (and on the covers, if any) a title distinct 189 from that of the Document, and from those of previous versions 190 (which should, if there were any, be listed in the History section 191 of the Document). You may use the same title as a previous version 192 if the original publisher of that version gives permission. 193 B. List on the Title Page, as authors, one or more persons or entities 194 responsible for authorship of the modifications in the Modified 195 Version, together with at least five of the principal authors of the 196 Document (all of its principal authors, if it has fewer than five), 197 unless they release you from this requirement. 198 C. State on the Title page the name of the publisher of the 199 Modified Version, as the publisher. 200 D. Preserve all the copyright notices of the Document. 201 E. Add an appropriate copyright notice for your modifications 202 adjacent to the other copyright notices. 203 F. Include, immediately after the copyright notices, a license notice 204 giving the public permission to use the Modified Version under the 205 terms of this License, in the form shown in the Addendum below. 206 G. Preserve in that license notice the full lists of Invariant Sections 207 and required Cover Texts given in the Document's license notice. 208 H. Include an unaltered copy of this License. 209 I. Preserve the section Entitled "History", Preserve its Title, and add 210 to it an item stating at least the title, year, new authors, and 211 publisher of the Modified Version as given on the Title Page. If 212 there is no section Entitled "History" in the Document, create one 213 stating the title, year, authors, and publisher of the Document as 214 given on its Title Page, then add an item describing the Modified 215 Version as stated in the previous sentence. 216 J. Preserve the network location, if any, given in the Document for 217 public access to a Transparent copy of the Document, and likewise 218 the network locations given in the Document for previous versions 219 it was based on. These may be placed in the "History" section. 220 You may omit a network location for a work that was published at 221 least four years before the Document itself, or if the original 222 publisher of the version it refers to gives permission. 223 K. For any section Entitled "Acknowledgements" or "Dedications", 224 Preserve the Title of the section, and preserve in the section all 225 the substance and tone of each of the contributor acknowledgements 226 and/or dedications given therein. 227 L. Preserve all the Invariant Sections of the Document, 228 unaltered in their text and in their titles. Section numbers 229 or the equivalent are not considered part of the section titles. 230 M. Delete any section Entitled "Endorsements". Such a section 231 may not be included in the Modified Version. 232 N. Do not retitle any existing section to be Entitled "Endorsements" 233 or to conflict in title with any Invariant Section. 234 O. Preserve any Warranty Disclaimers. 235 236 If the Modified Version includes new front-matter sections or 237 appendices that qualify as Secondary Sections and contain no material 238 copied from the Document, you may at your option designate some or all 239 of these sections as invariant. To do this, add their titles to the 240 list of Invariant Sections in the Modified Version's license notice. 241 These titles must be distinct from any other section titles. 242 243 You may add a section Entitled "Endorsements", provided it contains 244 nothing but endorsements of your Modified Version by various 245 parties--for example, statements of peer review or that the text has 246 been approved by an organization as the authoritative definition of a 247 standard. 248 249 You may add a passage of up to five words as a Front-Cover Text, and a 250 passage of up to 25 words as a Back-Cover Text, to the end of the list 251 of Cover Texts in the Modified Version. Only one passage of 252 Front-Cover Text and one of Back-Cover Text may be added by (or 253 through arrangements made by) any one entity. If the Document already 254 includes a cover text for the same cover, previously added by you or 255 by arrangement made by the same entity you are acting on behalf of, 256 you may not add another; but you may replace the old one, on explicit 257 permission from the previous publisher that added the old one. 258 259 The author(s) and publisher(s) of the Document do not by this License 260 give permission to use their names for publicity for or to assert or 261 imply endorsement of any Modified Version. 262 263 264 5. COMBINING DOCUMENTS 265 266 You may combine the Document with other documents released under this 267 License, under the terms defined in section 4 above for modified 268 versions, provided that you include in the combination all of the 269 Invariant Sections of all of the original documents, unmodified, and 270 list them all as Invariant Sections of your combined work in its 271 license notice, and that you preserve all their Warranty Disclaimers. 272 273 The combined work need only contain one copy of this License, and 274 multiple identical Invariant Sections may be replaced with a single 275 copy. If there are multiple Invariant Sections with the same name but 276 different contents, make the title of each such section unique by 277 adding at the end of it, in parentheses, the name of the original 278 author or publisher of that section if known, or else a unique number. 279 Make the same adjustment to the section titles in the list of 280 Invariant Sections in the license notice of the combined work. 281 282 In the combination, you must combine any sections Entitled "History" 283 in the various original documents, forming one section Entitled 284 "History"; likewise combine any sections Entitled "Acknowledgements", 285 and any sections Entitled "Dedications". You must delete all sections 286 Entitled "Endorsements". 287 288 289 6. COLLECTIONS OF DOCUMENTS 290 291 You may make a collection consisting of the Document and other 292 documents released under this License, and replace the individual 293 copies of this License in the various documents with a single copy 294 that is included in the collection, provided that you follow the rules 295 of this License for verbatim copying of each of the documents in all 296 other respects. 297 298 You may extract a single document from such a collection, and 299 distribute it individually under this License, provided you insert a 300 copy of this License into the extracted document, and follow this 301 License in all other respects regarding verbatim copying of that 302 document. 303 304 305 7. AGGREGATION WITH INDEPENDENT WORKS 306 307 A compilation of the Document or its derivatives with other separate 308 and independent documents or works, in or on a volume of a storage or 309 distribution medium, is called an "aggregate" if the copyright 310 resulting from the compilation is not used to limit the legal rights 311 of the compilation's users beyond what the individual works permit. 312 When the Document is included in an aggregate, this License does not 313 apply to the other works in the aggregate which are not themselves 314 derivative works of the Document. 315 316 If the Cover Text requirement of section 3 is applicable to these 317 copies of the Document, then if the Document is less than one half of 318 the entire aggregate, the Document's Cover Texts may be placed on 319 covers that bracket the Document within the aggregate, or the 320 electronic equivalent of covers if the Document is in electronic form. 321 Otherwise they must appear on printed covers that bracket the whole 322 aggregate. 323 324 325 8. TRANSLATION 326 327 Translation is considered a kind of modification, so you may 328 distribute translations of the Document under the terms of section 4. 329 Replacing Invariant Sections with translations requires special 330 permission from their copyright holders, but you may include 331 translations of some or all Invariant Sections in addition to the 332 original versions of these Invariant Sections. You may include a 333 translation of this License, and all the license notices in the 334 Document, and any Warranty Disclaimers, provided that you also include 335 the original English version of this License and the original versions 336 of those notices and disclaimers. In case of a disagreement between 337 the translation and the original version of this License or a notice 338 or disclaimer, the original version will prevail. 339 340 If a section in the Document is Entitled "Acknowledgements", 341 "Dedications", or "History", the requirement (section 4) to Preserve 342 its Title (section 1) will typically require changing the actual 343 title. 344 345 346 9. TERMINATION 347 348 You may not copy, modify, sublicense, or distribute the Document 349 except as expressly provided under this License. Any attempt 350 otherwise to copy, modify, sublicense, or distribute it is void, and 351 will automatically terminate your rights under this License. 352 353 However, if you cease all violation of this License, then your license 354 from a particular copyright holder is reinstated (a) provisionally, 355 unless and until the copyright holder explicitly and finally 356 terminates your license, and (b) permanently, if the copyright holder 357 fails to notify you of the violation by some reasonable means prior to 358 60 days after the cessation. 359 360 Moreover, your license from a particular copyright holder is 361 reinstated permanently if the copyright holder notifies you of the 362 violation by some reasonable means, this is the first time you have 363 received notice of violation of this License (for any work) from that 364 copyright holder, and you cure the violation prior to 30 days after 365 your receipt of the notice. 366 367 Termination of your rights under this section does not terminate the 368 licenses of parties who have received copies or rights from you under 369 this License. If your rights have been terminated and not permanently 370 reinstated, receipt of a copy of some or all of the same material does 371 not give you any rights to use it. 372 373 374 10. FUTURE REVISIONS OF THIS LICENSE 375 376 The Free Software Foundation may publish new, revised versions of the 377 GNU Free Documentation License from time to time. Such new versions 378 will be similar in spirit to the present version, but may differ in 379 detail to address new problems or concerns. See 380 http://www.gnu.org/copyleft/. 381 382 Each version of the License is given a distinguishing version number. 383 If the Document specifies that a particular numbered version of this 384 License "or any later version" applies to it, you have the option of 385 following the terms and conditions either of that specified version or 386 of any later version that has been published (not as a draft) by the 387 Free Software Foundation. If the Document does not specify a version 388 number of this License, you may choose any version ever published (not 389 as a draft) by the Free Software Foundation. If the Document 390 specifies that a proxy can decide which future versions of this 391 License can be used, that proxy's public statement of acceptance of a 392 version permanently authorizes you to choose that version for the 393 Document. 394 395 11. RELICENSING 396 397 "Massive Multiauthor Collaboration Site" (or "MMC Site") means any 398 World Wide Web server that publishes copyrightable works and also 399 provides prominent facilities for anybody to edit those works. A 400 public wiki that anybody can edit is an example of such a server. A 401 "Massive Multiauthor Collaboration" (or "MMC") contained in the site 402 means any set of copyrightable works thus published on the MMC site. 403 404 "CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0 405 license published by Creative Commons Corporation, a not-for-profit 406 corporation with a principal place of business in San Francisco, 407 California, as well as future copyleft versions of that license 408 published by that same organization. 409 410 "Incorporate" means to publish or republish a Document, in whole or in 411 part, as part of another Document. 412 413 An MMC is "eligible for relicensing" if it is licensed under this 414 License, and if all works that were first published under this License 415 somewhere other than this MMC, and subsequently incorporated in whole or 416 in part into the MMC, (1) had no cover texts or invariant sections, and 417 (2) were thus incorporated prior to November 1, 2008. 418 419 The operator of an MMC Site may republish an MMC contained in the site 420 under CC-BY-SA on the same site at any time before August 1, 2009, 421 provided the MMC is eligible for relicensing. 422 423 424 ADDENDUM: How to use this License for your documents 425 426 To use this License in a document you have written, include a copy of 427 the License in the document and put the following copyright and 428 license notices just after the title page: 429 430 Copyright (c) YEAR YOUR NAME. 431 Permission is granted to copy, distribute and/or modify this document 432 under the terms of the GNU Free Documentation License, Version 1.3 433 or any later version published by the Free Software Foundation; 434 with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. 435 A copy of the license is included in the section entitled "GNU 436 Free Documentation License". 437 438 If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, 439 replace the "with...Texts." line with this: 440 441 with the Invariant Sections being LIST THEIR TITLES, with the 442 Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST. 443 444 If you have Invariant Sections without Cover Texts, or some other 445 combination of the three, merge those two alternatives to suit the 446 situation. 447 448 If your document contains nontrivial examples of program code, we 449 recommend releasing these examples in parallel under your choice of 450 free software license, such as the GNU General Public License, 451 to permit their use in free software. 452