A a web developer you need many skills and be fluent in many languages. All the languages I use for web development can be (and are) coded by hand.
Extensible Hypertext Markup Language
This is the implementation of HTML in XML. It is a semantic language that is used define the presentational structure of a web document. Wrapping text in markup gives added meaning to that text. For instance one can define paragraph, headlines lists and such. HTML is stateless, it does not 'remember' information across (re)loads. It's probably the best known computer language.
A relatively young programming language that is rapidly evolving and growing. It's easy to code and drives the logic in almost every webpage today. Powerful so-called libraries exist that provide programmers with pre-built functionality, which can be easily added to web documents. Contrary to popular belief it has little to do with Java.
DOM
The Document Object Model is more a system than a language. It allows to access, create and modify the objects in a webpage. It uses the object-oriented syntax of JavaScript and has a tree structure. JavaScript uses the HTML DOM to work with a webpage.
Cascading Style Sheets
Using this language a programmer is able to determine and modify what the presentation of a document, i.e. what the elements of a document look like. This is where most of the graphical design part is implemented.
PHP: Hypertext Preprocessor
This language is used to implement the logic of a website on the server side. It allows easy integration of databases, state handling through sessions, includes and lots, lots more.
Structured Query Language
This language is used to manipulate databases (typically on the server side).
Scalable Vector Graphics
This XML 'dialect' can be used to produce scriptable vector graphics. Except on Mozilla browsers a plugin is needed for display.
XML User Interface Language
This XML 'dialect' is used to build graphic frontends for applications / extension on the Mozilla platform. The frontends of Firefox and Thunderbird are written in this language.