- Thomas Harriot (1560-1621)
- Born in England.
- He was instrumental in extending and codifying the theory of equations.
- He was the first to use > and to indicate greater than and less than.
- Felix Hausdorff (1862-1942)
- Born in Germany.
- He developed the branch of mathematics known as topology.
- He formaulated a maximal principle in general set theory.
- Jacques Herbrand (1908-1931)
- Born in France.
- He formaulated a theory which established a link between quantification theory and sentential logic.
- Charles Hermite (1822-1901)
- Born in France.
- He applied elliptic functions to find solutions of the quintic equation and of Lamé’s differential equation..
- He discussed the theory of associated covariants in binary quantics and the theory of ternary quantics
- Heron (Hero of Alexandria) (fl. 62 CE)
- Born in Egypt.
- His formula provides the area of a triangle when the lengths of the three sides are known, but the height is not known.
- David Hilbert (1862-1943)
- Born in Prussia.
- He solved all the known problems of algebraic invariants.
- He introduced sweepng developments and new areas for research in algebraic topography.
- Hipparchus of Rhodes ca. 180 – ca. 125 BCE)
- Born in Greece.
- His mathematical computations to chart the sun, moon, and stars led to his being named the founder of trigonometry.
- He is also considered the founder of Greek astronomy.
- Hippias (fl. ca.420 BCE)
- Born in Greece.
- He invented a curve called the quadratrix, by the means of which an angle can be divided into any given ratio.
- Hippocrates of Chios (fl. 2nd half of 5th century BCE)
- Born in Greece.
- He is credited with the first exposition which developed the theorems of geometry and logically from a few given axioms or postulates, in Elements.
- He formulated the quadrature of the lune, that is, the construction of a square having area equal to that of the original plane figure, using only a compass and a straightedge.
- John de Holywood (Sacrobosco) (ca.1200 – ca.1256)
- Born in England.
- His work on arithmetic was a standard authority for many years
- Hypathia (370-414 CE)
- Born in Egypt.
- Very little is known of her work, although it is believed that she was an algebraist.
- She seemed to have had an interest in conic sections.