Web development is a broad term for the work involved in developing a web site for the Internet (World Wide Web) or an intranet (a private network). This can include web design, web content development, client liaison, client-side/server-side scripting, web server and network security configuration, and e-commerce development.
Mobile application development is the process by which application software is developed for small low-power handheld devices such as personal digital assistants, enterprise digital assistants or mobile phones. These applications are either pre-installed on phones during manufacture, or downloaded by customers from various mobile software distribution platforms.
A scripting language is a command set for controlling some specific piece of hardware, software, or operating system, often with rudimentary and in some cases more advanced programming-like control flow constructs, and is almost always usable from a stored format such as a simple text file, a section of read-only persistent storage in an embedded device, a deck of punched cards, or other mechanism.