THOMAS EDISON
Self-taught American inventor and pioneer industrialist Thomas Alva Edison set up a laboratory in his basement at the age of ten.
During his lifetime Edison rose to become a folk hero and one of America's most prolific inventors.
Apart from inventing the phonograph and hundreds of other applicances, he is best known for inventing the electric light bulb in 1879.
After thousands of hours and research and experiments, using carbonized thread, Edison made an electric lamp which burned for 40 hours.
In 1882, Edison opened his first commercial lighting station in New York, marking the beginning of the electric lighting industry in America.

ALEXANDER GRAHAM BELL
This Scottish-born scientist is best known for inventing the telephone.
In 1865 Bell conceived of the idea to transmit speech by electric waves.
It took another 10 years for the principle to be developed and one hot June day in 1876 the first sentence was successfully transmitted by wire.
By 1877 the Bell Telephone Company came into being.
But Bell didn't stop there.
In 1880 he established the Volta Laboratory in Washington D.C., where Bell and his colleagues refined the phonograph invented by Thomas Edison.
He also improved education for the deaf by carrying forward the work of his father, Alexander Melville Bell, who created an alphabet with symbols representing every vocal sound.

MADAME CURIE
French scientists Marie Curie and her husband Pierre Curie's research in isolating polonium and radium marked the beginning of a new era in the study of atomic structure and radioactivity.
In 1903 the Curies shared the Nobel Prize for physics and after her husband's death, Marie was named to her husband's chair in physics at the Sorbonne.
In 1911 she was once again awarded the Nobel Prize and became the first person ever to receive a Nobel Prize for both physics and chemistry.
She headed the Pasteur Institute and a radioactivity laboratory at the University of Paris.

ALBERT EINSTEIN
Albert Einstein, physicist, philosopher and humanitarian, developed the theory of relativity.
As a child, Einstein showed no early signs of genius.
His father ran a small electro-chemical plant with his uncle, who introduced him to algebra and geometry.
Einstein's interest was drawn to theoretical physics, but he often skipped classes at the Federal Polytech school in Zurich, preferring to work on his own.
In 1905 Einstein published four papers of major importance in the journal Annalen der Phyik, including the first documentation on the velocity of light and his theory of relativity.
In the 1920's and 30s he lectured abroad.
In 1941, with the onset of World War II, Einstein immigrated to the United States.
A vocal pacifist, Einstein was concerned about the social consequences of scientific inventions such as nuclear energy.

JONAS SALK
Scientist Jonas Edward Salk is mostly known for developing the first vaccine against polio, though during Salk's early years as a scientist he workedfor the Army and also developed a vaccine against influenza.
By 1952 Salk and his group at Harvard University developed a way to separate the polio virus and Nuse it as an immunizing tool against the disastrous disease.