Today, computer systems aggregate trillions of tweets in search of commercial opportunities. However, the data is mined not only in commercial interests – it can be used by large companies to surprise their clients and for many other purposes.

Nevertheless, selling data is just a tiny part of Twitter’s income, as its largest share of profits is derived from advertising. Now Twitter decided to increase the figures and acquired Chris Moody’s analytics company Gnip for $130m a year ago.

It is known that Google and Facebook have built their businesses around sharing information, but the concerns are raised over their control of the private and public data, which is an area fraught with ethical and reputational risk. In the meantime, not all Twitter users realize that they are addressing the world, or the company that wants to listen in to their tweets. For most of the users, their audience is their followers. Although Twitter users can’t choose who follow them, they can shape their following by blocking or muting nuisance or abusive users. However, when you use a hashtag or address another user via Twitter handle, this may be regarded as the intention to publish a tweet it for a wider audience. As a result, Twitter takes these moves into account when distributing its data.

Another potential use for Twitter data is using geolocation and language algorithms. The service can match its users to some corporation’s database of customers in order to provide targeted advertising. In this case, the profiles can be matched, for instance, by using emails. Twitter also resells information for other social networks, including Tumblr and Foursquare. The company guarantees that this is done in a completely anonymized fashion, i.e. it doesn’t share private data.

Geolocation and programs monitoring aggressive or negative reactions could be used to monitor football crowds, for example. In this particular case, tweets could help assess the reaction of fans during and after a match. This may be helpful for police to decide where to deploy resources in combating public disturbance. In the meantime, information is about the crowd, which is not a means for police to target individual fans.

While Twitter doesn’t share the content of direct messages, the company considers all their other musings entirely public property. Remember about that.