two javascript The Definitive Guide

• 1, JavaScript programs are written using the Unicode character set. Unicode is ASCII and Latin-1 supercomputer, and supports almost all on Earth in the language.
• 2, JavaScript is case-sensitive language. HTML is not case sensitive
• 3, neat line indentation, to improve the readability of the code
• 4, JavaScript identifier must: start a letter, underscore _, dollar sign $
• 5, js not at all a line break is filled semicolon: Only in the absence of a semicolon can not resolve the code of normal time, js will complement semicolon
• 6, js data types: primitive types, object type
• 7, primitive types: numeric, string, boolean, null, undefined
• 8, function: It is an object having an associated executable code 33