Pages and post are 2 different content types in wordpress.

Page

  • A page can be defined as a permenant content which defines an website and is usually part of the menu or the link on homepage. Example will make it more clear. Like About Us, Contact Us, Links,  are all pages which are fixed and usually dont have a comments option on them.
  • Also the information on pages is vital and doesnot change with time.
  • They are fixed and usually are a part of the menu or site navigation links. Pages don’t have categories and tags.

Posts

  • Posts are something that all bloggers are looking to do. Give their information and related stuffs here.
  • Posts are catagorized and have tags.
  • Posts sometimes become outdated with time and need to be unpublished.