Font Categories: Typefaces can be divided into two main categories: serif and sans serif. Serifs comprise the small features at the end of strokes within letters. The printing industry refers to typeface without serifs as sans serif (from French sans, meaning without), or as grotesque (or, in German, grotesk). Source | More Info

Line Height: This property determines the amount by which the height of each element's line box is increased or decreased. Basically it is not a set measurement, but a calculation. In CSS, line-height is the difference between the values of line-height and font-size for a given element. The line-height property specifies the logical height of an inline element. This is the height used in the vertical alignment of inline elements and the construction of line boxes. It defines the height of the inline box for a given element. It determines the amount by which the height of each element's linebox is increased or decreased. Source | More Info

PHP: PHP is a scripting language originally designed for producing dynamic web pages. PHP is a widely-used general-purpose scripting language that is especially suited for web development and can be embedded into HTML. It generally runs on a web server, which is configured to take PHP code as input and create web page content as output. It can be deployed on most web servers and on almost every operating system and platform free of charge. PHP is installed on over 20 million websites and 1 million web servers. Source | More Info

CSS: Cascading Style Sheets (CSS) is a style sheet language used to describe the presentation (that is, the look and formatting) of a document written in a markup language. Its most common application is to style web pages written in HTML. CSS is designed primarily to enable the separation of document content from document presentation, including elements such as the colors, fonts, and layout. This separation can improve content accessibility, provide more flexibility and control in the specification of presentation characteristics, enable multiple pages to share formatting, and reduce complexity and repetition in the structural content (such as by allowing for tableless web design). CSS can also allow the same markup page to be presented in different styles for different rendering methods, such as on-screen, in print, by voice (when read out by a speech-based browser or screen reader) and on Braille-based, tactile devices. While the author of a document typically links that document to a CSS stylesheet, readers can use a different stylesheet, perhaps one on their own computer, to override the one the author has specified. CSS specifies a priority scheme to determine which style rules apply if more than one rule matches against a particular element. In this so-called cascade, priorities or weights are calculated and assigned to rules, so that the results are predictable. The CSS specifications are maintained by the World Wide Web Consortium (W3C). Source | More Info