Escape sequence,also known as HTML Character Entity,are a method of presenting special characters.
Escape sequences start with an ampersand(&) and end with a semicolon(;).The identifier can be either an entity name(an abbreviated text name for the character) or a number sign (#) followed by a numeric(decimal) code for the character. The numeric code can also be a hex value, designated by adding the letter "x" following the number sign in the escape sequence. The numeric code in the escape sequence(either decimal or hex) corresponds to the character's code point in the coded character set declared for the page.