Camel case is often used as a naming convention in computer programming, but is an ambiguous definition due to the optional capitalization of the first letter. Some programming styles prefer camel case with the first letter capitalised, others not. For clarity, this article calls the two alternatives upper camel case (initial uppercase letter, also known as Pascal case) and lower camel case (initial lowercase letter, also known as dromedary case). Some people and organizations, notably Microsoft, use the term camel case only for lower camel case. Pascal case means only upper camel case.
Camel case is distinct from Title Case, which capitalises all words but retains the spaces between them, and from Tall Man lettering, which uses capitals to emphasize the differences between similar-looking product names such as "predniSONE" and "predniSOLONE". Camel case is also distinct from snake case, which uses underscores interspersed with lowercase letters (sometimes with the first letter capitalized). A combination of snake and camel case (identifiers Written_Like_This) is recommended in the Ada 95 style guide.