Short answers, pulled from the story.
Salieri did not poison Mozart. The symptoms of Mozart's final illness do not indicate poisoning, and historians regard the two composers as at least mutually respectful peers. Salieri vehemently denied the accusations throughout his life, and the widespread public belief in the story contributed to his nervous breakdowns in later years.
Salieri composed more than 37 operas over a career spanning from 1770 to 1804. Among his most successful works were Armida (1771), La fiera di Venezia (1772), Les Danaïdes (1784), La grotta di Trofonio (1785), Tarare (1787), Axur re d'Ormus (1788), and Falstaff (1799). His opera Axur became his greatest international success and was performed as far as South America in 1824.
Salieri's pupils included Ludwig van Beethoven, Franz Schubert, Franz Liszt, Johann Nepomuk Hummel, and Franz Xaver Wolfgang Mozart. He taught most students free of charge, crediting the generosity his own teacher Florian Leopold Gassmann had shown him as a penniless orphan.
Salieri served as director of the Italian opera at the Habsburg court from 1774 to 1792, and as Austrian imperial Kapellmeister from 1788 to 1824. As Kapellmeister he was responsible for music at the court chapel and its attached school, a post he held for thirty-six years until his official retirement.
Peter Shaffer's 1979 play Amadeus, and its 1984 film adaptation directed by Miloš Forman, revived Salieri's name after roughly a century of obscurity but depicted him as a Machiavellian villain who worked to destroy Mozart's career. F. Murray Abraham won the Academy Award for Best Actor for the film role. The exposure prompted renewed interest in Salieri's actual music, even though the dramatic portrayal was heavily fictionalized.
Salieri was born on the 18th of August 1750 in Legnago, south of Verona, in the Republic of Venice. He died in Vienna on the 7th of May 1825 at the age of 74 and was buried at the Matzleinsdorfer Friedhof on the 10th of May; his remains were later transferred to the Zentralfriedhof.