PHP for WordPress (Crash Note)

PHP is a programming language. It’s also called server scripting language or general-purpose scripting language. PHP stands for Hypertext Preprocessor. Especially PHP is popular for Web Development, we can easily show dynamical HTML output with PHP.


  • Some time double quotation and single quotation play different roles in PHP.
  • Double quotation able to identify variable, single quotation can’t.
  • For execution double quotation take longer time than Single quotation.
  • No closing tag require in PHP.

Output in PHP

  • output show by the echo
  • output show by printf
  • decimal number can control by %05d
  • float by number can control by %.2f


Spaceship operator <=>

isset() alternative – Null coalescing operator ??