Naming

Names allow to identify variables, functions, types, labels and properties of objects. Rules for naming:

first character may be letters, underscore _, dollar sign allowed but not recomended
subsequent characters may be letters, digits, dollar signs, or underscore characters
letters may be ASCII characters a-z, A-Z or unicode characters
names are case sensitive, for example x and X are different variables
name must not match the reserved word
there are naming conventions

String आँtxt = "My text";

naming conventions

identifier type	description
package	Package name is always written in all-lowercase ASCII letters and should be one of the top-level domain names like com. For example, org.springframework.boot.
class interface	Class/interface names should be nouns, in mixed case with the first letter of each internal word capitalized. For example, SpringApplication.
method	Methods should be verbs, in mixed case with the first letter lowercase, with the first letter of each internal word capitalized. For example,identityHashCode
variable	Variable names are in mixed case with a lowercase first letter. For example, beanNameGenerator. In android java code style prefix s can be used for static class members, prefix m can be used for class members. For example, sMySingleton or mMyField Common names for temporary variables are i, j, k, m, and n for integers; c, d, and e for characters.
constant	Constants should be all uppercase with words separated by underscores. For example, DEFAULT_REACTIVE_WEB_CONTEXT_CLASS.