At present, in America and Britain two different forms of what has originally been one and the same language are spoken. George Bernard Shaw once spoke of England and America as two great countries separated by the same language. Even after four hundred years, the language of the past and the present has remained more or less the same. After American Revolution in 1775, Thomas Jefferson, who was ridiculed in London for his use of the word "belittle" in 1787, felt the need for their own language. Britishers could not digest Americanisms such as "antagonize, to advocate, bamboozle, calculate, contact, demote, to loan, OK, placate," etc. They treated all the new American coinages as "the uncouth expressions of the Yankee dialect." A sharp reaction had set in against British English in the eighteenth century and Americans chose to go their own way. With the serious efforts of Noah Webster in his Dictionary of the English Language(1828) and The American Spelling Book (1783), HL Men ken in his The American Language (1919) and George Philip Krapp in his two-volume work The English Language of America (1925), American English has got its own identity.

In more than three centuries, which have passed since the first English settlements were made in America, the American English (AE) and the British English (BE) have developed in divergent ways. Many old usages of English characteristic of seventeenth century have survived in standard American English. Besides, AE has developed new ways of speech partly through different conditions of life and partly through many influences from other languages. Apart from the differences in the shades of meaning of English vocabulary, there is a primary difference between AE and BE in pronunciation.
Spelling
The following are some of the important spelling variations in the AE and BE: 1.In AE the letter "l" is not usually doubled in an unstressed syllable.
BRITISH ENGLISH AMERICAN ENGLISH
Cancelled Canceled
Chilli Chili
Councillor Councilor
Counsellor Counselor
Jeweller Jeweler
Install Instal
Levelling Leveling
Libellous Libelous
Marvellous Marvelous
Panellist Panelist
Traveller Traveler
2. Some words ending in " -re " are written as "-er" in AE.
BRITISH ENGLISH AMERICAN ENGLISH
Calibre Caliber
Centre Center
Fibre Fiber
Litre Liter
Manoeuvre Manoeuver
Metre Meter