A Uniform Resource Locator (URL), colloquially termed a web address, is a reference to a web resource that specifies its location on a computer network and a mechanism for retrieving it. A URL is a specific type of Uniform Resource Identifier (URI), although many people use the two terms interchangeably. URLs occur most commonly to reference web pages (http), but are also used for file transfer (ftp), email (mailto), database access (JDBC), and many other applications. Most web browsers display the URL of a web page above the page in an address bar. A typical URL could have the form http://www.example.com/index.html, which indicates a protocol (http), a hostname (www.example.com), and a file name (index.html).
Google URL Shortener, also known as goo.gl, is a discontinued URL shortening service offered by Google. It was launched in December 2009, initially used for Google Toolbar and Feedburner. Later Google launched a separate website goo.gl and opened up to public in September 2010.The user could access a list of URLs that had been shortened in the past after logging in to their Google Account. And the user could see additional details via the "details" link next to any shortened URL, where public, real-time analytics data, including traffic over time, top referrers, and visitor profiles could be found. For security, Google added automatic spam system detection based on the same type of filtering technology used in Gmail. The service has not been accepting new users since April 13, 2018 and Google discontinued the service for existing users on March 30, 2019. Links previously created still redirect to their previous destination. It was succeeded by Firebase Dynamic Links, but existing links won't become Dynamic Links automatically.
The vertical bar ( | ) is a computer character and glyph with various uses in mathematics, computing, and typography. It has many names, often related to particular meanings: Sheffer stroke (in logic), verti-bar, vbar, stick, vertical line, vertical slash, bar, pike, or pipe, and several variants on these names. It is occasionally considered an allograph of broken bar (see below).