=== Auto-allocation === For many operators that will write to a provided array or string (and does not use it for reading), you can pass null instead of a array or string in order to automatiaclly allocate a new one of the correct size. The new object is writable, not executable, and uses the current VM mode if possible or local if global is not valid. These operators include: copy cvrs cvs dictstack execstack readline (probably also some others) === Binary object format === There is a new type available, which is type 15 for dictionaries. The format is the same as an array, and is coded as an even number of entries being alternating keys and values. === Removed === Some features of level 3 PostScript are removed from Computer PostScript. These features include: * The job server and all operators and parameters related to it have been removed from Computer PostScript. * The %disk0% etc file I/O devices are removed. * The system parameters that are only relevant for printers are removed, which are /PageCount and /PrinterName. (The /Pagecount page device parameter still exists in Computer PostScript.) * The system parameters /FactoryDefaults, /StartJobPassword, /StartupMode, and /SystemParamsPassword are removed. The startup mode, default values for settings, and ability to change them, is implementation-dependent and may be external to the PostScript interpreter. Settings changed using the standard PostScript mechanisms (if allowed) are only set while the program is executing; the settings are lost once the program is terminated. * If the implementation is not approved by Adobe, then the /LicenseID system parameter is either blank or a URI. * The /JobName user parameter no longer exists. * DSC is not used. An implementation of Computer PostScript MUST treat DSC comments like any other comment (causing them to be ignored). === Standard fonts === Computer PostScript requires only the following thirteen standard PostScript fonts (it is allowed to have more, but they are optional): * Courier (Regular, Oblique, Bold, Bold Oblique) * Helvetica (Regular, Oblique, Bold, Bold Oblique) * Times (Roman, Italic, Bold, Bold Italic) * Symbol They need not be the official Adobe fonts; other fonts are possible, if the names mentioned above are available as aliases for them.