Okay, "Glossary" may not be the best description for this section. I'm trying to explain terms in a [over-]simplified way so that the beginning Drupaller can get her/his arms around Drupal.

You might also want to look at the handbook section on Basic Terminology.

A node is a container for stuff (sorry for the technical term). Some of that stuff is the content you create. Drupal itself creates a few nodes for its own stuff.

A module is a way to extend the functionality of Drupal. It is usually a lot of programmed code (usually in php) and, usually, a style sheet (CSS). For example, if you want to include meta tags to describe your content, you would add on the "Nodewords" module (also known as "Meta Tags").

A theme is a means of manipulating and describing how you want your content displayed to your visitors. This includes elements such as your header, icons, block layout, etc. It also includes programming and style sheets.

A server is (generally) a computer that provides services to the Internet. These services may be things like running the database or managing the gathering and dissemination of information.

A browser is the "program" that you use to display content from the Internet. In reality, it is usually a set of programs, not a single one; it is also a set of tables (e.g. settings) that are used to control its display. Examples are Internet Explorer, Netscape, and Firefox. This operates on the client, or user, side of the presentation.

HyperText Markup Language (HTML) is the standardized language of the web. It has its own "vocabulary," consisting of tags, elements, and descriptors. A tag is the basic component and is used to say, "The following content is to be displayed according to these rules." An example of a tag is a level one heading (<H1>). Most tags can have additional information to tell the browser more specifically how you want it to render the content. This specification is called an element. Most elements require more information to make them work, this is the descriptor, which really should be called "value." For example, if you want that heading centered, you would use the "align" element and give it a descriptor (value) of "center." So , completely constructed it would look like this: <H1 ALIGN="CENTER">.

A Taxonomy is a way of characterizing stuff. It can be used for grouping, selecting, and protecting stuff. Many people who are new to Drupal think this is a very difficult subject (admittedly, we can make it so), however, virtually all of us had an introduction to taxonomy in school: classifying living creatures (i.e. the Linnaean taxonomy). In that taxonomy, we classified living things according to kingdoms (plant or animal), phylum, class, and so on, down to genus and species. In reality there is an additional classification below species; sub-species (animals) or varietal (plants). [Oh, yeah, I vaguely remember that! That's a taxonomy?]

In Drupal, the highest level of taxonomy description is the "vocabulary;" it is used for defining the terms, or tags, that actually end up on your stuff to be used for the various purposes. In the above example, think of "Living things" as the vocabulary. Each vocabulary has one or more "terms" that are used to tag (i.e. define, or describe) your stuff. Terms may be hierarchical; that is they may exist in levels. Genus and species would be hierarchical terms. The vocabulary is assigned to input types (e.g. stories, recipes); terms are assigned to a given piece of content (e.g. "Groundbreaking Research on Macadamia Nut Yields" or "My Fabulous Macadamia Brittle"). Notice that I said "terms" - plural - because an individual node may have more than one term associated with it; for example, the "Research" news article may be assigned to "Nuts," "Trees," and "Harvesting." It could then be viewed through any of those terms (or keywords).

Breadcrumbs is a term borrowed from Hansel and Gretel, who left crumbs of bread along their path so they could find their way back out of the forest. In current computer parlance, it refers to the section, usually near the top of the page, that shows the path you followed to locate the current page. For example, it might show Home > Macadamia Nuts > Current Events > News Articles, meaning that you started at the home page, clicked on "Macadamia Nuts" in the menu, then selected "Current Events" in the sub-menu, and finally selected, "News Articles."

A database is a container for containers. It is a collection of related "tables" that are generally used for a single application (such as Drupal). A table is a collection of data used for a specific purpose within that application, such as identifying users. Within a table, each individual grouping of data is referred to as a row (or in traditional terms, a "record"). Each row is identified by one or more keys that allow easy retrieving of the row. Each row is then broken down into columns (often called fields, although this is more appropriate for forms on which the data is displayed). A column holds a specific piece of information for the row, such as a user name or country.

Now, just to complicate things a bit, some times we describe the collection of item-related table rows with a collective term. One such term is "node." For example, information about a page on your site may exist in several tables; yet we describe all of this as a "node."

Still confused? Let's try to relate this to an example you're probably familiar with. Let's relate this to your windows computer.

Your [hard] disk (or disc) is sort of like a database; it is a collection of your data. On that disk, you have folders; they are analogous to tables within a database. Inside those folders, you have documents or programs; these relate to rows. Within the document (e.g. a Word document), you have paragraphs; these are much like columns.

Okay, let's add to the analogy a little. Word or Lotus 1-2-3 would be your theme, as they describe and manipulate the content before it is displayed to you. It's a bit of a stretch for several reasons, but you can then think of Windows itself as your browser, since it is responsible for the final rendering of the content to you.

Does that help a little?

The Structured Query Language (SQL) is a standard specification for how database engines locate data that you want. An example might be SELECT country FROM user_profile WHERE username = "Nancy"; this would get the value from the column "country" in the "user_profile" table using column "username" as the key.