Facebook is to allow its users to create a hierarchy of friends within their profiles - in a move that threatens to complicate the already delicate social etiquette that governs the site.

As part of new controls to be introduced in the social networking site's privacy settings, Facebook users will be given the option of banning certain friends from seeing what they are up to and accessing sensitive information in their profile.

The change will mean that, for instance, a particular friend - a former partner, say - could be prevented from seeing that a person had changed their relationship status, while others could be banned from knowing the person's political or religious views.

Facebook also said it would dramatically expand the number of people to whom a person could expose their personal information by introducing an option to allow not only friends but friends of friends too to gain access to their profile.

Facebook: The beginner’s guide

Forced to sign up by repeated friend requests? Hit the virtual ground running with our virtual guide

Multimedia

• Facebook section - full coverage

BACKGROUND

• Careless Facebook users ‘open to identity theft’

• Ten essential Facebook accessories

• Parents are turning into online spies

• Networkers who click with 1,000 ‘friends’

Related Links

• Hey, Facebook, just let go of me

• Is Facebook finally losing its glow?

• Web socialites succumb to ‘Facebook fatigue’

At present, the maximum exposure that a profile can be given displays the profile to all the person's friends, and members of any network of which they are a part - typically private groups set up by employers, schools or universities. There will remain no option to expose one's profile to all Facebook users.

Facebook, which has nearly 40 million users worldwide, has grown enormously in popularity, but some have complained about the problems of social etiquette it has posed - for instance, whether one should accept 'friend requests' from people whom one has not seen for years, and where there is no desire to restore contact.

The site is hoping its users will appreciate being given greater flexibility to customise the privacy settings which they attach to their profiles.

A new feature similar to instant messaging services, called Facebook Chat, which will allow friends to communicate instantly with others who are online, will also be unveiled in the next few weeks, the site said.

Issues relating to privacy have been responsible for some of the hiccups Facebook has experienced since it was opened to the general public in late 2006.

In June last year, Facebook was forced to admit that a flaw meant users may have unwittingly been exposing certain personal details - such as their sexual orientation and religious beliefs - to others on the site.

In December, the site apologised for introducing a new feature that would have allowed a user's actions elsewhere on the web - for instance their puchases on Amazon - to be broadcast to their friends without consent.

The feature, called Beacon, has now been changed so that users have to 'opt in' before it is activated.

Explore Tech & Web

• Personal Tech

• The Web

• Gadgets & Gaming