Gmail

Gmail is a free email service provided by Google. As of 2019, it had 1.5 billion active users worldwide. A user typically accesses Gmail in a web browser or the official mobile app. Google also supports the use of email clients via the POP and IMAP protocols.

At its launch in 2004, Gmail provided a storage capacity of one gigabyte per user, which was significantly higher than its competitors offered at the time. Today, the service comes with 15 gigabytes of storage. Users can receive emails up to 50 megabytes in size, including attachments, while they can send emails up to 25 megabytes. In order to send larger files, users can insert files from Google Drive into the message. Gmail has a search-oriented interface and a "conversation view" similar to an Internet forum. The service is notable among website developers for its early adoption of Ajax.

Google's mail servers automatically scan emails for multiple purposes, including to filter spam and malware, and to add context-sensitive advertisements next to emails. This advertising practice has been significantly criticized by privacy advocates due to concerns over unlimited data retention, ease of monitoring by third parties, users of other email providers not having agreed to the policy upon sending emails to Gmail addresses, and the potential for Google to change its policies to further decrease privacy by combining information with other Google data usage. The company has been the subject of lawsuits concerning the issues. Google has stated that email users must "necessarily expect" their emails to be subject to automated processing and claims that the service refrains from displaying ads next to potentially sensitive messages, such as those mentioning race, religion, sexual orientation, health, or financial statements. In June 2017, Google announced the end to the use of contextual Gmail content for advertising purposes, relying instead on data gathered from the use of its other services.

Storage
There are also storage limits to individual Gmail messages. Initially, one message, including all attachments, could not be larger than 25 megabytes. This was changed in March 2017 to allow receiving an email of up to 50 megabytes, while the limit for sending an email stayed at 25 megabytes. In order to send larger files, users can insert files from Google Drive into the message.
 * 1) On April 1, 2004, Gmail was launched with one gigabyte (GB) of storage space, a significantly higher amount than competitors offered at the time.
 * 2) On April 1, 2005, the first anniversary of Gmail, the limit was doubled to two gigabytes of storage. Georges Harik, the product management director for Gmail, stated that Google would "keep giving people more space forever."
 * 3) In October of 2007, Gmail increased storage to 4 gigabytes, after recent changes from competitors Yahoo & Microsoft.
 * 4) On April 24, 2012, Google announced the increase of storage included in Gmail from 7.5 to 10 gigabytes ("and counting") as part of the launch of Google Drive.
 * 5) On May 13, 2013, Google announced the overall merge of storage across Gmail, Google Drive, and Google+ Photos, allowing users 15 gigabytes of included storage among three services.
 * 6) On August 15, 2018, Google launched Google One, a service where users can pay for additional storage, shared among Gmail, Google Drive and Google Photos, through a monthly subscription plan. As of 2021, storage of up to 15 gigabytes is included, and paid plans are available for up to 2 terabytes for personal use.

Interface

 * Main article: Gmail interface

The Gmail user interface initially differed from other web-mail systems with its focus on search and conversation threading of emails, grouping several messages between two or more people onto a single page, an approach that was later copied by its competitors. Gmail's user interface designer, Kevin Fox, intended users to feel as if they were always on one page and just changing things on that page, rather than having to navigate to other places.

Gmail's interface also makes use of 'labels' (tags) – that replace the conventional folders and provide a more flexible method of organizing emails; filters for automatically organizing, deleting or forwarding incoming emails to other addresses; and importance markers for automatically marking messages as 'important'.

In November 2011, Google began rolling out a redesign of its interface that "simplified" the look of Gmail into a more minimalist design to provide a more consistent look throughout its products and services as part of an overall Google design change. Majorly redesigned elements included a streamlined conversation view, configurable density of information, new higher-quality themes, a resizable navigation bar with always-visible labels and contacts, and better search. Users were able to preview the new interface design for months prior to the official release, as well as revert to the old interface, until March 2012, when Google discontinued the ability to revert and completed the transition to the new design for all users.

In May 2013, Google updated the Gmail inbox with tabs which allow the application to categorize the user's emails. The five tabs are: Primary, Social, Promotions, Updates, and Forums. In addition to customization options, the entire update can be disabled, allowing users to return to the traditional inbox structure.

In April 2018, Google introduced a new web UI for Gmail. The new redesign follows Google's Material Design, and changes in the user interface include the use of Google's Product Sans font. Other updates include a Confidential mode, which allows the sender to set an expiration date for a sensitive message or to revoke it entirely, integrated rights management and two-factor authentication.

On 16 November 2020, Google announced new settings for smart features and personalization in Gmail. Under the new settings users were given control of their data in Gmail, Chat, and Meet, offering smart features like Smart Compose and Smart Reply.

On 6 April 2021, Google rolled out Google Chat and Room (early access) feature to all Gmail users.

On 28 July 2022, Google rolled out Material You to all Gmail users.

Platforms
Gmail is available as a web app for all modern browsers and as an app for iOS and Android.