A signature block (often abbreviated as signature, sig block, sig file, or just sig) is a block of text automatically appended at the bottom of an e-mail message, Usenet article, or forum post. This has the effect of "signing off" the message. A common practice is to have one or more lines containing some brief information on the author of the message. Wikipedia does not yet have an article with this exact name. ... Usenet is a distributed Internet discussion system that evolved from a general purpose UUCP network of the same name. ... Gaia Online, the largest English language forum-based community as of April 2005 — powered by a modified version of phpBB. An Internet forum is a facility on the World Wide Web for holding discussions, or the web application software used to provide the facility. ...

Information usually contained in a sig block includes the poster's name, phone number, postal address and email address, along with other contact details if required, such as URLs for sites owned or favoured by the author. A witty or profound quotation is often included (occasionally automatically generated by such tools as fortune or Quotator), or an ASCII art picture. Strict rules of capitalization are not followed (example, it is very en vogue to write "tel" instead of "Tel" to designate telephone). Among some groups of people it has been common to include self-classification codes, though the practice is waning. A Uniform Resource Locator, URL (spelled out as an acronym, not pronounced as earl), or Web address, is a standardized address name layout for resources (such as documents or images) on the Internet (or elsewhere). ... fortune is a simple program that displays a random message from a database of quotes. ... ASCII art, an artistic medium relying primarily on computers for presentation, consists of pictures pieced together from characters (preferably from the 95 printable characters defined by ASCII). ...

E-mail and Usenet

Since by definition these blocks are added automatically to a message, usually regardless of its content, there are guidelines of netiquette regarding their size. The most common guideline, called the McQuary limit, is a size of no more than four lines of less than eighty columns each. This keeps the overall size of the message down, conserving bandwidth as well as the time required to read the message, and ensures that eighty-column terminals (the most common terminal width by far) can display the sig block properly, allowing for programs that reserve the last column for a continuation character; using all eighty columns for text can result in a character wrapping to the next line. Netiquette (neologism, a portmanteau formed from Internet etiquette) is a catch-all term for the conventions of politeness recognised on Usenet, in mailing lists, and on other electronic forums such as internet message boards. ... Bandwidth is a measure of frequency range, measured in hertz, of a function of a frequency variable. ... A computer terminal is an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system. ...

The formatting of the sig block is prescribed somewhat more firmly: it should be displayed as plain text in a fixed-width font (no HTML, images, or other rich text), and must be delimited from the body of the message by a single line consisting of exactly two hyphens, followed by a space, followed by the end of line (i.e., "-- n"). This latter prescription, which goes by many names, including "sig dashes", "signature cut line", and "sig-marker", allows software to automatically mark or remove the sig block as the receiver desires. A correct delimiter is required for a news posting program to receive the Good Netkeeping Seal of Approval. Computer files can be divided into two broad categories: binary and text. ... An excerpt of HTML code with syntax highlighting In computing, HyperText Markup Language (HTML) is a markup language designed for the creation of web pages with hypertext and other information to be displayed in a web browser. ... The Rich Text Format (often abbreviated to RTF) is a document file format that has been continually developed by Microsoft since 1987 for cross-platform document interchange. ... The Good NetKeeping Seal of Approval or GNKSA is designation that indicates a piece of Usenet software for end-user use meets a minimum set of posting standards. ...

However, whether due to ignorance or disregard for these guidelines, a great many people use sig blocks that are either formatted improperly or larger than these suggested dimensions. In past decades, such practice was referred to as warlording, named for one particular Usenet regular who openly flouted the guidelines with sig blocks stretching to many hundreds of lines of ASCII art on messages with little or no relevant content.

Many corporations have internal policies requiring outgoing emails to have lengthy "signatures" appended to them, listing dozens of contact methods, disclaiming legal liabilities, notifying of virus scanning methods, and so forth. These corporate signatures are almost universally large (often larger than the message itself), and composed without regard for the netiquette guidelines described above; they are seen as obnoxious and irritating by many who receive them. In computer security technology, a virus is a self-replicating/self-reproducing-automation program that spreads by inserting copies of itself into other executable code or documents. ...

The use of top-posting (with fullquoting) compounds the problem by causing messages to have ever-lengthening tails of garbage hanging off their end, as various corporate disclaimers, ads from free mail services, mailing list footers, and the like get added. Top-posting means replying to a message above the original message. ...

Internet forums

On web forums, the rules are often less strict on how a signature block is formatted, as Web browsers typically are not operated within the same constraints as text interface applications. Users will typically use a "signature" text area in their given profile for input, which can then allow a user to turn off signatures. Depending on the board's capabilities, signatures may range from a simple line or two of text to an elaborately-constructed HTML piece. Images are often allowed as well, including dynamically updated images, usually hosted remotely and modified by a PHP script. Gaia Online, the largest English language forum-based community as of April 2005 — powered by a modified version of phpBB. An Internet forum is a facility on the World Wide Web for holding discussions, or the web application software used to provide the facility. ... It has been suggested that Comparison of web browsers be merged into this article or section. ... For images in Wikipedia, see Wikipedia:Images. ... PHP is a scripted programming language that can be used to create websites. ...

Fidonet

In Fidonet these signatures usually include the address of the originator of the message and are called "origins". The FidoNet logo FidoNet is an inter-connecting file and message transport system that was used by bulletin board systems. ...

External links

• Quotator