English is a Germanic Language of the Indo-European Family. It is the second most spoken language in the world. The history of the language can be traced back to the arrival of three Germanic tribes to the British Isles during the 5th Century AD. Angles, Saxons and Jutes crossed the North Sea from what is the present day Denmark and northern Germany. The inhabitants of Britain previously spoke a Celtic language. This was quickly displaced. Most of the Celtic speakers were pushed into Wales, Cornwall and Scotland. One group migrated to the Brittany Coast of France where their descendants still speak the Celtic Language of Breton today. The Angles were named from Engle, their land of origin. Their language was called Englisc from which the word, English derives.

Since the 16th Century, because of the contact that the British had with many people from around the world, and the Renaissance of Classical learning, many words have entered the language either directly or indirectly. New words were created at an increasing rate. Shakespeare coined over 1600 words. This process has grown exponentially in the modern era. Borrowed words include names of animals (giraffe, tiger, zebra), clothing (pajama, turban, shawl), food (spinach, chocolate, orange), scientific and mathematical terms (algebra, geography, species), drinks (tea, coffee, cider), religious terms (Jesus, Islam, nirvana), sports (checkmate, golf, billiards), vehicles (chariot, car, coach), music and art (piano, theatre, easel), weapons (pistol, trigger, rifle), political and military terms (commando, admiral, parliament), and astronomical names (Saturn, Leo, Uranus).

Languages that have contributed words to English include Latin, Greek, French, German, Arabic, Hindi (from India), Italian, Malay, Dutch, Farsi (from Iran and Afghanistan), Nahuatl (the Aztec language), Sanskrit (from ancient India), Portuguese, Spanish, Tupi (from South America) and Ewe (from Africa).

The rapid international expansion of the British and the American economies has spread English throughout the globe. It is now the second-most spoken language in the world after Mandarin Chinese. As such, it has bred a variety of regional “Englishes” (generally referred to as English dialects) and English-based creoles and pidgins.

The British Isles is the most linguistically diverse area in the English-speaking world. Significant changes in accent and dialect may occur within one region. Three major divisions are normally classified as Southern English dialects, Northern English dialects and Scottish English and the closely related dialects of the Scots language.

There is also Irish English and the form of English used in Wales. The various English dialects differ in the words that have been borrowed from other languages. The Scottish and Northern dialects include many words originally borrowed from Old Norse and a few borrowed from Gaelic.

While there are many differences between the various English dialects, modern-day communications and mass media have reduced these differences significantly. In addition, speakers of very different dialects may modify their speech, and particularly vocabulary, towards Standard English.

Hiberno-English is the form of the English language used in Ireland. The standard spelling and grammar are the same as British English but in the spoken language, there are some unique characteristics.

American English has both spelling and grammatical differences from British English, some of which arose as part of an attempt to rationalize the English spelling used by British English at the time. Unlike many 20th century language reforms (e.g. Turkey's alphabet shift and Norway's spelling reform), the American spelling changes were not driven by government, but by textbook writers and dictionary makers.

The first American dictionary was written by Noah Webster in 1828. At the time, America was a relatively new country and Webster's particular contribution was to show that the region spoke a different dialect from Britain; hence he wrote a dictionary with many spellings differing from the standard. Many of these changes were initiated unilaterally by Webster. Many words are shortened and differ from other versions of English. Conversely, American English can sometimes favor more wordy or elongated versions of British English, as in transportation for transport.

Canadian English is the form of English used in Canada. In many respects, the spelling of Canadian English lies in between British English and American English. However, the spoken language is much closer to American English than British English. It is also influenced by Canadian French, as Canada has both English and French as official languages.

Caribbean English refers to the different forms of the English language spoken in the Caribbean. In the Caribbean, there is a great deal of variation in the way English is spoken. A simple statement, "I don't know" would be stated, "Me 'na know."

Oceanic English is similar in many respects to British English but it also borrows from American English. (For example, it uses truck instead of lorry, and freeway rather than motorway.) Australian English is most similar to New Zealand English, although the difference is immediately obvious to a speaker from either country.

Indian English is a catchall phrase for dialects or varieties of English spoken widely in India. The language that Indians are taught in schools is essentially British English and in particular, spellings follow British conventions. However, the British left India in 1947 and as a result, many phrases that the British may consider antique are still popular in India. Official letters continue to include phrases like: "please do the needful," "you will be intimated shortly" and "your obedient servant." Older writers who made creative (and comical) use of now obsolete forms of colloquial English, like P. G. Wodehouse, are immensely popular too, as is cricket terminology like "googly" and "bouncer".

Manglish is the version of the English language spoken in Malaysia, and is very similar to Singlish in Singapore. Theoretically, English as spoken in Malaysia is based on British English, and British spelling is generally followed. However, American English is having a strong influence. Since 1968, Malay or Bahasa Malaysia has been the country's sole official language; thus, while English is still widely used, many Malay words have become part of common usage in English. The other major languages spoken in Malaysia - Mandarin, Cantonese, Hokkien and Tamil, also strongly influence the spoken English.

Singlish is the dialect of the English language as spoken colloquially in Singapore. Singlish formally takes after British English (in terms of spelling and abbreviations), although naming conventions are a mixture of American and British ones. For instance, local media have "sports pages" (“sport” in British English) and "soccer coverage" (the use of the word "soccer" is not common in British media).