in my opinion the 5 significant events for the guardian are:

2015

The Guardian unveils a new site for readers in the UK and across the world. (A US version launched in October 2014, Australia in November).

Katharine Viner is appointed Guardian editor-in-chief.

David Pemsel succeeds Andrew Miller as chief executive of GMG.

2007

GU undergoes a redesign with interactive content, images, graphics and video given greater importance.

In October the Guardian launches guardianamerica.com, a new site designed to meet the needs of the paper’s growing US audience.

GMG sells 49.9% of Trader Media Group to Apax Partners in a deal that values TMG at £1.3 billion.

2004

In March, digital editions of the papers launched, allowing access to articles, images and adverts as they appeared in print. In July the Soulmates dating service interactive website goes live. The paper also introduces a weekly tabloid edition aimed at students and distributed throughout UK university campuses.

1999

The Guardian Unlimited (GU) network of websites is launched in January. It consists of News Unlimited, Football Unlimited, Cricket Unlimited and Jobs Unlimited. By March 2001 GU has over 2.4 million unique users, making it the most popular UK newspaper website. The first official ABCe statistics in October identify GU as having 10.2 million page impressions a month.

1967

Guardian Newspapers Ltd and The Manchester Evening News Ltd are formed as wholly owned subsidiary companies of The Manchester Guardian and Evening News Ltd, each with their own board of directors.