Twitter was one of the first micro-blogging services and uses text messages as its medium.
Usually text messages only travel between two people but Twitter ensures each one reaches a wider audience. Messages sent to Twitter are echoed to your own page and to all the friends signed up to get them.
The 140 character limit in text messages imposes an austere brevity and many use Twitter to keep friends and colleagues up to date with where they are, who they are meeting and what they are thinking.
When out and about, updating a Twitter blog is easier than doing a web-based blog update.
Since Twitter launched in mid-2006 many competitors have sprung up including Pownce, Jaiku and Yelp.
MOBLOGGING
When it first emerged, blogging was very much an activity done sat in front of a PC. Moblogging, as its name implies, takes this mobile.
This can mean that a blog post or entry is written and sent from a laptop via a wi-fi hotspot in a cafe or from a capable mobile phone. As long as it is done on the hoof, it qualifies.
Many of the first to blog with a mobile simply took pictures of what they saw and who they met while out and about. Many mobloggers use tiny programs that automatically send any snap they take to their blog.
As camera phones have become inescapable the number of moblogs and mobloggers has escalated.
Now any blog is as likely to contain snaps sent from a phone as it is longer text entries composed in a moment of repose. Pretty much all blogging software contains tools that will take content from any and every device.
VIDEOBLOGGING
As you might expect video blogging adds moving pictures to the format.
Video clips can be shot with a mobile phone, webcam, handheld or static camera. Clips can be snapshots of what just happened, diary-like entries or quasi-professionally produced shows.
Many bloggers who make their living from their journal use short video shows as a means to keep their audience entertained and up to date.
The popularity of portable media players, such as the iPod, has substantially grown the audience for such shows.
Some, such as Justin.tv, send out a constant stream of video from a camera they wear to show what they are up to each and every minute.
SOCIAL NETWORKS
For many the hardest part of blogging is building up an audience interested in what that person has to say or has snapped.
Social networking sites such as MySpace, Facebook and Bebo solve this problem as they deliver a ready-made audience - many of whom will be people you already know.
Most of these sites let users upload photos, videos and text - just like any blogging site.
Many of these sites are now starting to add extras and add-ons that let people step up the interaction with the folk with whom they have connected.
LIFECASTING
This is the ultimate endpoint of the move to sharing your life with other people.
While some video bloggers stream images of where they go, lifecasting tries to create a more permanent, searchable, record of a person's life.
It involves capturing as much data as possible about everything someone does. Not just recording and archiving face-to-face or phone conversations but also creating an indexed database of documents, text messages e-mails, pictures - everything.
An attempt to record part of a life in this way is being tried by Microsoft researcher Gordon Bell as part of the MyLifeBits project.
His archive now contains more than 120,000 e-mails, almost 60,000 photographs, hours of phone call recordings and much more data about his life.
Just as important as grabbing the data is indexing it properly and creating links between all the elements to give an overview of how a life is being lived.
^ Back to top | BBC Sport Home | BBC Homepage | Contact us | Help | ©
~RS~q~RS~~RS~z~RS~07~RS~)