How many template options available when creating a new apex class in Salesforce?

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An Apex class is a template or blueprint from which Apex objects are created. Classes consist of other classes, user-defined methods, variables, exception types, and static initialization code. Once successfully saved, class methods or variables can be invoked by other Apex code, or through the SOAP API (or AJAX Toolkit) for methods that have been designated with the webService keyword.