Syndactyly (from Greek συν- = "together" plus δακτυλος = "finger") is a condition wherein two or more digits are fused together. It occurs normally in some mammals, such as the siamang and kangaroo, but is an unusual condition in humans.

Syndactyly can be simple or complex.

Syndactyly can be complete or incomplete.

Complex syndactyly occurs as part of a syndrome (such as Apert syndrome) and typically involves more digits and with complex syndactyly.^{[clarification needed]}

Fenestrated syndactyly means the skin is joined for most of the digit but in a proximal area there is gap in the syndactyly with normal skin. This type of syndactyly is found in amniotic band syndrome.

Simple syndactyly can be full or partial, and is present at birth (congenital). In early human fetal development, webbing (syndactyly) of the toes and fingers is normal. At about 16 weeks of gestation, apoptosis takes place and an enzyme dissolves the tissue between the fingers and toes, and the webbing disappears. In some fetuses, this process does not occur completely between all fingers or toes and some residual webbing remains.

Charles F. Goldfarb is known as the father of SGML and is a co-inventor of the concept of markup languages. In 1969 Charles Goldfarb, leading a small team at IBM, developed the first markup language, called Generalized Markup Language, or GML. In an interview with Web Techniques Magazine editor Michael Floyd, Dr. Goldfarb explains that he coined the term GML to be an initialism for the three researchers, Charles Goldfarb, Ed Mosher and Ray Lorie who worked on the project.

In 1974, he designed SGML and subsequently wrote the first SGML parser, ARCSGML. Goldfarb went on working to turn SGML into the ISO 8879 standard, and served as its editor in the standardization committee.

Goldfarb holds an LL.B. from Harvard Law School. He worked at IBM's Almaden Research Center for many years and is now an independent consultant based in Saratoga, California.

Leonardo di ser Piero da Vinci (Italian pronunciation: [leoˈnardo da ˈvintʃi]  pronunciation (help·info); April 15, 1452 – May 2, 1519, Old Style) was an Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist, and writer whose genius, perhaps more than that of any other figure, epitomized the Renaissance humanist ideal. Leonardo has often been described as the archetype of the Renaissance Man, a man of "unquenchable curiosity" and "feverishly inventive imagination". He is widely considered to be one of the greatest painters of all time and perhaps the most diversely talented person ever to have lived. According to art historian Helen Gardner, the scope and depth of his interests were without precedent and "his mind and personality seem to us superhuman, the man himself mysterious and remote". Marco Rosci points out, however, that while there is much speculation about Leonardo, his vision of the world is essentially logical rather than mysterious, and that the empirical methods he employed were unusual for his time.