Learning online

I study this page in order to make some comments on web links and pedagogy. For context I took a course with good grades which taught the use of Lagrangian methods. I have used Hamiltonians successfully. Yet I feel that I do not understand Lagrangian mechanics.

Wikipedia generally comes closer as a source where you can learn about something than any other site, with occasional exceptions for specialized sites.

In a web article technical terms are often used. Some of the audience will not know the meanings of these terms. It is common practice and good practice to include a link to an authoritative description of the term with enough information to proceed with the current page. In the case of Wikipedia these links are frequently to a Wikipedia article. The common use of such links often fails in one of two ways:

An article may need passing reference to the notion of mathematical group. The need may require only the leanest understanding of a group. The article on groups may have category theory as a prerequisite. (Wikipedia does not.) Guidance is usually missing as to how much you need to know before you return to the referring page. Occasionally is it possible to refer to a particular subsection of a page with implicit or explicit instructions that you need to understand that one ‘sub-notion’. The student may discover prerequisites in the referred page as defined in that page.

There is a vague notion of ‘parasitic’ that relates these ideas.


Establish some sort of clue easily accessible to the reader about the nature of this link—perhaps link color.