This layout is used as default in the current main operating systems. U.S. keyboards are used not only in the United States, but also in other English-speaking places (e.g., Australia, English Canada, Hong Kong, New Zealand, South Africa, Malaysia, the Philippines and India), excluding the United Kingdom and Ireland, which use a UK standard instead. The US keyboard can be found worldwide in the stores.

The US keyboard layout has a second Alt key instead of the AltGr key and does not use any dead keys, and thus offers no way of inputting any sort of diacritic or accent; this makes it unsuitable for all but a handful of languages. On the other hand, the US or UK keyboard layout is occasionally used by programmers in countries where the keys for []{} are located in less convenient positions on the locally customary layout.

On some keyboards the enter key is bigger than traditionally and takes up also a part of the line above, more or less the area of the traditional location of the backslash key (\). In these cases the backslash is located on alternative places. It can be situated one line above the default location, on the right of the equals sign key (=).Sometimes it's placed one line below its traditional situation, on the right of the apostrophe key (') (on these cases the enter key is narrower than usual on the line of its default location).It may also be two lines below its default situation, below the enter key, on the right of a narrower than traditionally right shift key.

Content is from wikipedia.org