Gmail interface

The Gmail interface makes Gmail unique amongst webmail systems for several reasons. Most evident to users are its search-oriented features and means of managing e-mail in a "conversation view" that is similar to an Internet forum.

An official redesign of the Gmail interface was rolled out on November 1, 2011 that simplified the look and feel of Gmail into a more minimalist design to provide a more consistent look throughout Google products and services as part of an overall design change.

Gmail makes use of Ajax, employing browser features such as JavaScript, keyboard access keys and Web feed integration.

Gmail allows users to conduct advanced searches using either the Advanced Search interface or through search operators in the search box. Emails can be searched by their text; by their ‘From’, ‘To’ and ‘Subject’ fields, by their location, date and size; by associated labels, categories and circles, by whether or not the message is read, and by whether or not the message has an attachment. There are also a large number of advanced search operators. By default, Gmail combines search terms with an invisible “AND”. Gmail allows the use of Boolean operators such as “OR” for finding messages that match at least one of the more search terms.

Gmail allows users to create rules (‘filters’) for the automatic organization of incoming mail. Filters are created using the Advanced Search interface using the same criteria as those used for searching. Gmail can perform any combination of the following actions upon an email that meets all the specified criteria in a filter:

Labels provide a flexible method of organizing emails since an email can have any number of labels (in contrast to a folder-based system in which an email can belong to only one folder). Labels are much like tags on a blog post. Labels can also do the work of folders if and email is moved to a label – this is the equivalent of applying a label to it as well as archiving it. By default, labels appear on the message list and can be customized with a color. Users can also create sub-labels beneath a label to create a hierarchy or nested labels. Labels can be used as a search criterion and all emails having a particular label can be viewed together through the side menu. Gmail has often received praise for replacing the limitations of hierarchical folders with the flexibility of labels.

...
Wikipedia