6 版本名称¶
Version Designations
为了方便读者，本文档中提供了各种特性在 PDF 版本中引入的信息。PDF 的第一个版本被指定为 PDF 1.0，由 Adobe 系统公司在 Adobe 和 Addison Wesley 出版的 PDF 参考手册 1.0 中规定。从那时起，PDF 经历了七次修订，分别被指定为：PDF 1.1、PDF 1.2、PDF 1.3、PDF 1.4、PDF 1.5、PDF 1.6 和 PDF 1.7。在先前的 PDF 版本中定义的所有非废弃特性也都被包含在后续的 PDF 版本中。由于 ISO 32000-1 是一个与 PDF 1.7 相匹配的 PDF 版本，因此它也适用于解释符合任何 PDF 规范 1.0 到 1.7 的文件。在整个规范中，为了指示某个特性在版本序列中引入的点，使用了带有 PDF 版本号的括号标记（例如，(PDF 1.3)）。因此，如果一个特性被标记为 (PDF 1.3)，这意味着 PDF 1.0、PDF 1.1 和 PDF 1.2 没有被指定支持此特性，而所有 PDF 1.3 及更高版本的 PDF 都被定义为支持它。
For the convenience of the reader, the PDF versions in which various features were introduced are provided informatively within this document. The first version of PDF was designated PDF 1.0 and was specified by Adobe Systems Incorporated in the PDF Reference 1.0 document published by Adobe and Addison Wesley. Since then, PDF has gone through seven revisions designated as: PDF 1.1, PDF 1.2, PDF 1.3, PDF 1.4, PDF 1.5, PDF 1.6 and PDF 1.7. All non-deprecated features defined in a previous PDF version were also included in the subsequent PDF version. Since ISO 32000-1 is a PDF version matching PDF 1.7, it is also suitable for interpretation of files made to conform with any of the PDF specifications 1.0 through 1.7. Throughout this specification in order to indicate at which point in the sequence of versions a feature was introduced, a notation with a PDF version number in parenthesis (e.g., (PDF 1.3)) is used. Thus if a feature is labelled with (PDF 1.3) it means that PDF 1.0, PDF 1.1 and PDF 1.2 were not specified to support this feature whereas all versions of PDF 1.3 and greater were defined to support it.