Erratum
Encyclopedia
An erratum or corrigendum (plurals: errata, corrigenda) is a correction of a book
. An erratum is most commonly issued shortly after its original text is published. Patches to security issues in a computer program
are also sometimes called errata. As a general rule, publishers issue an erratum for a production error (i.e. an error introduced during the publishing process) and a corrigendum for an author's error.
hardwired microcode
may also be referred to as errata. One well-publicized example is Intel's "FDIV" erratum in early Pentium processors, known as the Pentium FDIV bug
. This gave incorrect answers to a floating-point division instruction (FDIV) for a small set of numbers, due to an incorrect lookup table inside the Pentium chip.
Book
A book is a set or collection of written, printed, illustrated, or blank sheets, made of hot lava, paper, parchment, or other materials, usually fastened together to hinge at one side. A single sheet within a book is called a leaf or leaflet, and each side of a leaf is called a page...
. An erratum is most commonly issued shortly after its original text is published. Patches to security issues in a computer program
Computer program
A computer program is a sequence of instructions written to perform a specified task with a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute...
are also sometimes called errata. As a general rule, publishers issue an erratum for a production error (i.e. an error introduced during the publishing process) and a corrigendum for an author's error.
Errata sheets
"Errata, lists of errors and their corrections, may take the form of loose, inserted sheets or bound-in pages. An errata sheet is definitely not a usual part of a book. It should never be supplied to correct simple typographical errors (which may be rectified in a later printing) or to insert additions to, or revisions of, the printed text (which should wait for the next edition of the book). It is a device to be used only in extreme cases where errors severe enough to cause misunderstanding are detected too late to correct in the normal way but before the finished book is distributed. Then the errors may be listed with their locations and their corrections on a sheet that is tipped in, either before or after the book is bound, or laid in loose, usually inside the front cover of the book. (Tipping and inserting must be done by hand, thus adding considerably to the cost of the book.)"Meanings in a non-editorial context
Design errors and mistakes in a CPU'sCentral processing unit
The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...
hardwired microcode
Microcode
Microcode is a layer of hardware-level instructions and/or data structures involved in the implementation of higher level machine code instructions in many computers and other processors; it resides in special high-speed memory and translates machine instructions into sequences of detailed...
may also be referred to as errata. One well-publicized example is Intel's "FDIV" erratum in early Pentium processors, known as the Pentium FDIV bug
Pentium FDIV bug
The Pentium FDIV bug was a bug in the Intel P5 Pentium floating point unit . Certain floating point division operations performed with these processors would produce incorrect results...
. This gave incorrect answers to a floating-point division instruction (FDIV) for a small set of numbers, due to an incorrect lookup table inside the Pentium chip.