A guideline is a statement by which to determine a course of action. A guideline aims to streamline particular processes according to a set routine or sound practice. By definition, following a guideline is never mandatory. Guidelines are not binding and are not enforced.
Network technology in general, and the Internet in particular, have evolved by leaps and bounds.
energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat.
Story is a piece of prose fiction that typically can be read in one sitting and focuses on a self-contained incident or series of linked incidents.