1. A computer-implemented method for presenting custom variables to a user of a web analytics system, comprising: receiving an activity file of a web server, wherein the activity file includes activity file hit records that provide information about respective requests for documents made by visitors of web sites; identifying a custom variable tag of an activity file hit record in the activity file, wherein the activity file hit record is associated with a web site, wherein the custom variable tag is defined by an author of a document of the web site, and wherein the custom variable tag is assigned to a custom variable of the web site; extracting attribute-value pairs of the custom variable tag, wherein the attributes of the custom variable tag include at least a name attribute, a value attribute, and a scope attribute; storing the attribute-value pairs of the custom variable tag in a database hit record of a database, wherein the database includes a plurality of database hit records including a plurality of attribute-value pairs extracted from a plurality of activity file hit records; and preparing for presenting, to a user, one or more attribute-value pairs of a plurality of custom variable tags assigned to the custom variable of the web site, wherein the user is separate and distinct from the authors of the documents of the web site.