There are three sections here:
A Twitter Glossary
An Eccentric Twitter Glossary
A Torchwood Glossary including:
Torchwood Locations
Torchwood Characters and Actors
Torchwood Quotes
Twitter Glossary
These are some of the officially or semi-officially recognized Twitter terms:
Twitter - the Twitter service provided at http://www.twitter.com (and through various web and desktop based tools that access the Twitter databases by an API (Application Programming Interface).
Tweet - a 140 character message posted on the Twitter service which answers the question "What are you doing?". It may include plain text or text and URLs (or shortened URLs).
Tweeter or Twitterer - a person who Tweets.
Twitter Profile - the profile page of a Tweeter - this includes a main column showing recent Tweets, and a sidebar including short (160 character) biographical information, a profile picture, and statistics such as the number of people Following or being Followed by you.
Follower(s) - someone who signs up to receive/view the recent feeds of another Twitter user. Generally this is shown as a number which, when clicked, brings up the relevant list of Twitter users.
Followed By - the people a Twitterer is followed by. Generally this is shown as a number which, when clicked, brings up the relevant list of Twitter users.
Listed - an indication of which, and how many, lists a Twitterer has been included on.
Lists - a way to group Twitterers round a theme or grouping of your own choosing. Tweeters are able to optionally follow a whole list of people (by following the list rather than each individual Tweeter in turn).
Twitterati - a collective noun for in-the-know Twitter groupings and communities. Often these are opinion leading groups (e.g. media specialists, technology journalists, high profile Tweeters like Stephen Fry, Alyssa Milano etc).
@... - the @ symbol followed by a Twitter username usually denotes a response to a named Tweeter (and often to a specific Tweet). Any use of the @ symbol automatically triggers Twitter's databases to include a link to the username referenced so it also used to tag Tweets of interest to specific users.
DM (e.g. DM @...) - the prefix DM allows Twitterers to send Direct Messages to each other - these are a non public subset of Tweets.
RT (e.g. RT @...) - the prefix RT denotes a "ReTweet", effectively a forwarded or re-distributed message.
Hashtag or #... (e.g. #Torchwood or #Followfriday) - the # symbol denotes a 'hashtag" or tag for a specific tweet. This has a special status on Twitter and triggers Twitter to turn the #... into a link to all other Tweets that feature that hashtag. There are various services that track or help find hashtags including http://hashtags.org/ - site designed to list hashtags and featuring various hashtag information and http://tagal.us/ which collates user-contributed definitions of hashtags.
FollowFriday - Follow Friday is a tradition that appeared relatively recently as a personal type of directory service. People taking part in #FollowFriday (or #FF) tweet out recommendations of those Twitterers that would be interesting for others' to follow. This allows people to pick up personal recommendations for people in their interest/professional/hobby areas.
Tweeps - People who Tweet (see also Twitterers)
Trending or Trending Topic - On the Twitter service the sidebar shows a list of trending topics - these are topics being most discussed on Twitter. Popular real time events (news events, celebrity news, TV shows, hot topics for discussion) appear in this area of the site as do protest campaigns and, only very occasionally, well distributed spam hashtags.
Eccentric Twitter Glossary
Twitter has lots of highly personal invented terms associatted with it since Tweeters started trying to self-define actions on the site before the Twitter team could invent their own. Although Twitter rolls out features very slowly enthusiastic Tweeters continue to make up their own vocabularies. For instance according to sources cited in Business Week's April 2009 feature "How to Speak Twitter" this is an apparently legitimate glossary of Twitter terms (though I haven't seen many of these in use):
At Reply, or "@reply": A direct tweet sent to another Twitter user.
Dweet: Tweet sent while drunk
Hash Tag: The "#" sign. Allows Twitter users to group tweets by topic, making it easier to search particular conversations using Twitter Search.
Link: Including a URL in your tweet.
MisTweet: A tweet one later regrets.
ReTweet: To repost something that's already in the Twitter stream. Usually preceeded by "RT" and "@[username]," to give credit to the original poster.
SnapTweet: A tweet that includes a photo taken with a cell phone, uploaded to Flickr and posted to Twitter via snaptweet.com.
Twittcrastination: Procrastination brought on by Twitter use.
Twadd: To add someone as a friend or follower.
Twaigslist/Twebay: To sell something on Twitter.
Tweeter/Twitterer: Someone who uses Twitter.
TwinkedIn: Inviting friends made on Twitter to connect on LinkedIn.
Twittectomy: To remove someone from the list of people you follow.
Twitterati: The A-list twitterers everyone follows.
Twitterfly: Twitter's version of a social butterfly, marked by the extreme use of @ signs.
Twitterlooing: Twittering from the bathroom.
Twitterpated: Overwhelmed with Twitter messages.
Twittfeinated, Twigged Out, Twired: To be so hyped up on twittering that you cannot sleep.
Torchwood Glossary: The Runners and Riders
There are a few things that are useful to know about Torchwood when looking at these tweets, I'm adding some Children of Earth-specific terms (marked by an asterisk*) but most are generic to any Torchwood chatter on Twitter (or elsewhere).
Torchwood Locations
Cardiff - Torchwood is set in the Cardiff Bay (waterfront) area of modern day Cardiff. A map showing key regions is shown at the bottom of this section. The third season of Torchwood took part partly in Cardiff, partly in non-specific rural areas in South Wales, and partly in London in and around No 10 Downing Street and the Houses of Parliament
The Hub - is the eccentric underground office base for the Torchwood team. It is a concealed space near the (real life) Millennium Centre and built around a central atrium with facilities including holding cells for alien lifeforms, an autopsy room and refridgerated storage, file space, and some leisure/quasi accomodation space. It is never explicitly explained but is implied that Captain Jack lives at the Hub and that (in latter series) Ianto also frequently stays there. In series three (Children of the Earth) the Hub was destroyed.
The Rift - Torchwood's central fantasy element is the concept of a rift in space and time that runs through Cardiff. The Torchwood team must monitor and protect Cardiff, and indeed the Earth from any malevolent alien life forces or technologies that emerge through the rift.
Characters and Actors
These are the characters mentioned in Tweets during the time period I looked at and information is provided to allow comments to be understood in context. For a full run down of characters the BBC Torchwood site gives a full overview of the series three cast.
Captain Jack Harkness (AKA Captain Jack, AKA Jack) is the leader of Torchwood. He is explicitly omnisexual and cannot, apparently, ever die (unlike Doctor Who he self-heals rather than regenerating) though villians and accidents frequently cause him to lose his breath for a few minutes. His costume is based on a World War II military look and reflects the age and complex memories of the character. The character was first introduced in season one of the relaunched Doctor Who series in the episodes The Empty Child and The Doctor Dancers. Captain Jack is played by John Barrowman, an openly gay actor with a background in musical theatre. As well as Torchwood Barrowman appears on various BBC programmes, particularly those related to his musical work. He currently has an autobiography out and appears on several music recordings. He has a cult following partly because of his reputation for somewhat outrageous behaviour and partly because he has been unusually honest and eloquent in discussing his sexuality in the mainstream media. Ianto Jones was, initially, the "tea boy" and office administrator for Torchwood with duties including monitoring the secret entrance to the Hub and ordering team pizza. Ianto's commitment to Torchwood initially centres on the loss and anger he feels when his girlfriend, Lisa, is murdered by/turned into a Cyberman. Ianto, though heterosexual-identified, is attracted to Jack and forms a close emotional and sexual relationship with him that develops during season one and becomes a core part of the plot in seasons two, three and the radio episodes of the series. Ianto and Jack's relationship is a bedrock of the show's popularity for many fans.Gareth David-Lloyd plays Ianto and has a significant cult following among many fans that was not routinely acknowledged until series three's shock killing off of the character. Subsequent interviews with the actor suggest that the death of Ianto was not related to his own continued availability and that he was love the chance to continue playing the role. This has fuelled fan activity calling for the resurrection of Ianto and return of Gareth David-Lloyd to the Torchwood cast.
Gwen Cooper is the new recruit at the beginning of the first season of Torchwood. A police officer she joins the team after she begins investigating a case that has been taken off her, and colleague PC Andy Davidson's hands by the Torchwood team. She is a tough action orientated character whose boyfriend, Rhys Williams, plays a more traditionally feminine role to her erratic absences and work hours and Torchwood-obsessed schedule. However as the core female character in the series (and the only remaining female lead in season three) Gwen is also the emotional voice of Torchwood. Her role is that of (usually unofficial) second in command to Captain Jack, with whom she has also had an ongoing flirtation.Gwen is played by Eve Myles, an established Welsh actress with a substantial body of work in TV and theatre though she has not previously appeared in a role as high profile as Gwen. Eve has also appeared in an episode of Doctor Who as a maid able to hear the thoughts of alien spirits. Though her character is strong and feisty she does not seem to have attracted the same cult following as her colleagues. One tenant of the Torchwood myth is the idea that those who join the organization do not have particularly long or healthy lives. Key characters in seasons one and two, Tosh (an extremely high functioning computer genius) and Owen (a trained doctor and team medic/alien biologist), die before season three take place. Owen is mentioned by one Tweeter in the day that I observed #Torchwood as linearity is not a given in the age of DVD box sets and repeats across the globe. Her reference to Owen and Gwen sleeping together refers to a season two plot line. In season one an additional team member, Susie, dies (although she is, for a short period, revived twice) and, despite her short period on the show she does get mentioned by those watching early series DVDs from time to time.
Quotes
"you will never be a blip in time to me" - this quote refers to a conversation between Jack and Ianto in series three of Torchwood. Ianto, for the first time, explicitly voices his love and insecurity over his relationship with Jack. Ianto is concerned that his life is, and will be, so short compared to Jack's already-hundred+ years of life that he feels that he is just a short term connection who can be easily forgotten. Jack responds with this quote. It is romantic and, unlike many science fiction expressions of love, is both entirely accessible and very specific to the show and the characters. The phrase has been adopted by a number of Ianto Jones fan movements including the #Torchwood Tweeters and, in fan works such as this fanfiction story built around this quote (and another taken from a Radio 4 Torchwood play).