Camel Case

Camel case (stylized as camelCase or CamelCase; also known as camel caps or more formally as medial capitals) is the practice of writing compound words or phrases such that each word or abbreviation in the middle of the phrase begins with a capital letter, with no intervening spaces or punctuation. Common examples include "iPhone", "eBay", "FedEx", "DreamWorks", and "HarperCollins". It is also sometimes used in online usernames such as "JohnSmith", and to make multi-word domain names more legible, for example in advertisements.

Programming and coding\ The use of medial caps for compound identifiers is recommended by the coding style guidelines of many organizations or software projects. For some languages (such as Mesa, Pascal, Modula, Java and Microsoft's .NET) this practice is recommended by the language developers or by authoritative manuals and has therefore become part of the language's "culture".

Style guidelines often distinguish between upper and lower camel case, typically specifying which variety should be used for specific kinds of entities: variables, record fields, methods, procedures, types, etc. These rules are sometimes supported by static analysis tools that check source code for adherence.

The original Hungarian notation for programming, for example, specifies that a lowercase abbreviation for the "usage type" (not data type) should prefix all variable names, with the remainder of the name in upper camel case; as such it is a form of lower camel case.

Programming identifiers often need to contain acronyms and initialisms that are already in uppercase, such as "old HTML file". By analogy with the title case rules, the natural camel case rendering would have the abbreviation all in uppercase, namely "oldHTMLFile". However, this approach is problematic when two acronyms occur together (e.g., "parse DBM XML" would become "parseDBMXML") or when the standard mandates lower camel case but the name begins with an abbreviation (e.g. "SQL server" would become "sQLServer"). For this reason, some programmers prefer to treat abbreviations as if they were lowercase words and write "oldHtmlFile", "parseDbmXml" or "sqlServer". However, this can make it harder to recognise that a given word is intended as an acronym.