The Complete guide to geek holidays

Updated 02/01/16: New geek holidays added in January, February and December.

It's over. The year 2015 is finally finished -- and today we start to look to the year ahead, with all of our various best intentions, resolutions and goals for the next 365 days open before us. While you've got your calendar open, planning out vacation days or fitness targets or personal due dates, take a quick look at this handy guide to geek- and tech-related holidays, anniversaries, release dates, events and dates-of-note.

Intended to be a kind of living document, this list is by no means comprehensive but intended to be updated throughout the year with things we may have missed. It will also be available shortly as a Google calendar so you can easily add it or share it, which will also reflect defunct holidays or events that are no longer held. Know of a geek-worthy holiday that didn't make the list? Email or Tweet details to me, and I'll add it!

January

National Clean Up Your Computer Month: If you needed an excuse to clean your keyboard, back up your hard drive, clean your monitor or delete old files, well, here ya go.
1/2 National Science Fiction Day (Also, Isaac Asimov's birthday): Usually celebrated by reading Asimov or Philip K. Dick, or by watching any number of sci-fi movies.
1/3 J.R.R. Tolkien's birthday
1/4 Sir Isaac Newton's birthday (12/25 on the Julian calendar)
1/8 Roy Batty's Incept date (Blade Runner) Also: Stephen Hawking's birthday
1/12 50th Anniversary of Batman's premiere on ABC
1/15 Wikipedia Day: The anniversary of the day that Wikipedia launched in 2001, creating a helpful repository of information and answers. Celebrate by changing the Wiki entry for elephants or by not ignoring their donation page for once.
1/17 Ben Franklin's birthday
1/25 Macintosh Day: While Steve Jobs introduced the original Macintosh on Jan. 24th, 1984, the anniversary of the beige box-like PC is traditionally celebrated on the 25th.
1/25 – 1/31 Winter-een-mas: A week-long holiday created by Ctrl+Alt+Delete author Tim Buckley, Winter-een-mas is a "celebration of games and the gamers who play them." Participants celebrate the gaming community by exchanging game-related gifts and by gaming with friends.
1/26 Dungeons & Dragons Day: While Worldwide D&D Game Day is later in the year, some have pointed to this date as the official anniversary of the game.
1/28 Data Privacy Day: Intended to raise awareness of privacy issues, and to educate users about the importance of protecting their personal digital privacy, this is a good day to review social media settings and change passwords.

February

2/4 Facebook's 12th Birthday: The Zuck is asking for fans to celebrate #friendsday with stories about friendships that have made a difference in your life.
2/7 e Day: In mathematics, Euler's constant is the base of the natural logarithm and is represented by "e" which equals approximately 2.71828. This, naturally, means that Feb. 7th is "e" day -- not to be confused with eDay which is an Aussie initiative that raises awareness of electronic waste.
2/8 Clean Out Your Computer Day: Traditionally celebrated on the second Monday in February, this holiday is a second shot at keeping your computer clean and running quickly by clearing out all those useless files and downloads.
2/11 National Inventors' Day (Also, not coincidentally, Thomas Edison's birthday): The Gipper himself made this day, the anniversary of Edison's birthday, a day for the United States to recognize the contribution that inventors make throughout the world. Fun fact: Edison not only had a righteous middle name (Alva) but also held over 1,000 patents.
2/12 Darwin Day: Celebrated on the birthday of naturalist and geologist Charles Darwin, Darwin Day is celebrated around the world with discussions on Darwin's works, food and explorations of his theories.
2/14 Pris's Incept date (Blade Runner). Also: The end-of-the-world date according to Ghostbusters II. Bummer.
2/15 Galileo Galliei's birthday
2/19 Nicolaus Copernicus's birthday
2/20 Introduce a Girl to Engineering Day: Begun by the Society of Women Engineers (SWE), Introduce a Girl to Engineering Day is also celebrated on other days in late February (The National Society of Professional Engineer's DiscoverE program celebrates "Girl Day" on February 25th as part of the larger Engineers Week).
02/21 - 02/27 Engineers Week: A week-long event that celebrates the advancements made by engineers, and raises awareness of the need for skilled engineers. Global Day, a day to specifically celebrate the accomplishments of engineers, falls in this week on Feb. 24th.
2/22 World Thinking Day: Technically, World Thinking Day is a Girl Scouts holiday wherein girl and boy scouts spend time pondering on their sister and brother scouts throughout the world, with each year focusing on a different theme. This year, for the 90th anniversary of Thinking Day, the theme is "Connect." Celebrate by spending some time actually connecting with a friend, neighbor or family member.

2/27 Pokemon Day: The 20th Anniversary of Pikachu and Charmander. Celebrate by catching them all, naturally.

March

3/1 World Maths Day: An international event, World Maths Day is actually an online mathletic competition where participants play 60 second games. Think of it as a MMOG. But with math.
3/3 Alexander Graham Bell's birthday
3/4 Game Master's Appreciation Day: Members of the RPG community will want to spend this day showing gratitude to those who help guide them on their various quests. Also, theoretical physicist George Gamow's birthday and National Grammar Day.
3/8 Ralph H. Baer's birthday
3/10 International Day of Awesomeness: A day to "perform and celebrate feats of awesomeness!" Not coincidentally, also Chuck Norris's birthday.
3/11 Douglas Adams' birthday
3/14 Pi Day (Also, Albert Einstein's birthday): Naturally, a day to celebrate the mathematical constant of Pi, which has been calculated to over 1 trillion digits past its decimal point with the 'holiday' being celebrated since roughly 1988.
3/22 James T Kirks birthday (At least, it will be starting in 2233)
3/25 Tolkien Reading Day: An annual event to encourage people to read and share Tolkien's works; also sometimes celebrated as the Fall of Sauron day.
3/26 Earth Hour (Also, Leonard Nemoy's birthday): An annual event that encourages people to think about the planet... And turn off their non-essential lights and electrical devices for an hour as a symbol of commitment to environmental issues.
3/31 World Backup Day: Because the first rule of computing is still backup. The second rule of computing? Backup.

April

Mathematics Awareness Month: The entire month of April is dedicated to "recognizing the importance of mathematics" via essays and an annual poster with each year getting a different theme of focus.
4/4 Square Root Day: An unofficial holiday that is celebrated on days when the day and month are the square root of the year (hence 4/4/16). The next Square Root Day will not be until 5/5/2025.
4/5 Annual CSS Naked Day: Celebrated every year since 2006, this is a day that challenges websites to remove links to CSS files and show off the nitty gritty realities of HTML. (April 5th, 2063 is also "First Contact" marking the first Vulcan/human interaction).
4/12 Yuri's Night: Named for Yuri Gagarin, the first human to launch into space, Yuri's Night celebrates milestones in space exploration and is also sometimes called the "World Space Party."
4/16 Foursquare Day: Begun by fans of the Foursquare app in 2010, Foursquare Day celebrates the popular app via local events.
4/21 High Five Day: Started at the University of Virginia and held annually on the third Thursday in April, this day now encourages high-fives in the name of charity.
4/25 DNA Day: A day that commemorates the 1953 Nature article that published details on the structure of DNA; celebrates with essays and events.
4/27 Morse Code Day: Celebrated on the birthday of morse code inventor Samuel Morse, this is a good excuse to finally learn morse code.
4/30 Birth of the World Wide Web: On April 30th, 1993 CERN put the world wide web into public domain to ensure an open standard.
4/30 International Tabletop Day: A day to celebrate tabletop games, this holiday began only a few years ago courtesy of the Geek & Sundry YouTube channel. Celebrate by playing board or card games with groups of friends. Bonus points for streaming the sessions on YouTube.

May

5/1 CSS Reboot Day: A day for web professionals to launch web-based standards redesigns; celebrate by updating your website. (Also, Reduced Plancks Constant Day which... well, it's math so have fun with that).
5/2 Free Comic Book Day: Celebrated on the first Saturday in May, this year will be the 15th event to celebrate and encourage the love and reading of all manner of comic books.
5/4 Star Wars Day: Star Wars fans celebrate the franchise on this day by greeting everyone with "May the fourth be with you" -- a punny play on "the force." However, the first known reference to the term was actually a misspelled congratulations to Margaret Thatcher on the eve of her 1979 inauguration.
5/5 Revenge of the 5^th: Not one to be left out, the Dark Siders and Sith Lords can also revel in their love for the series by celebrating the day after Star Wars Day.
5/14 George Lucas's birthday
5/18 International Museum Day: Coordinated by the International Council of Museums and held every year since 1977, this themed day is dedicated to raising awareness of the importance of museums. This years theme is Museums and Cultural Landscapes.
5/21 Talk Like Yoda Day: The day you talk like Yoda, this is.
5/22 Ethernet invented. Also, the release date of Pac Man in 1980.
5/25 Geek Pride Day: A day of many events that celebrate all things worthy of geek love. Also, Towel Day for Douglas Adams fans (celebrated by carrying a towel, naturally) and The Glorious 25th of May for Terry Pratchett fans.
5/27 Wordpress released.

June

6/1 - 6/5 World Science Festival: A festival held by the Science Festival Foundation, with week long events in New York City as well as televised programs.
6/16 Captain Picard Day: Generally agreed upon as the correct day to represent Stardate 47457.1, this is the day that the Enterprise hosted schoolchildren and showed them what Starfleet was like in The Pegasus episode of The Next Generation.
6/18 Golden Ratio Day: Phi is the letter of the Greek alphabet used to represent the golden ratio, which equates to 1.618 numerically. (There is some debate about the appropriate date of this holiday.)
6/23 Alan Turing's birthday
6/28 Tau Day: It's not all about Pi -- there's also a day set aside for Tau, the circle constant based on radius (instead of diameter). Also, International Caps Lock Day which is celebrated again on Oct. 22nd.

July

7/2 World UFO Day: A day for folks to get together and watch the skies for signs of alien lifeforms, this holiday is also sometimes celebrated on June 24th (the day that aviator Kenneth Arnold reported the first UFO sighting) while July 2nd marks the date of the alleged 1947 UFO crash in Rosewell.
7/6 Take Your Webmaster to Lunch Day
7/10 Nikola Tesla's birthday
7/13 Embrace Your Geekiness Day: In case you missed Geek Pride Day.
7/14 Happy Ripping Day: Celebrates the anniversary and origin of the MP3
7/17 Yellow Pig Day: Princeton students in the 60's were given an assignment about the number 17 which somehow turned into a yellow pig/math themed day...Also, World Emjoi Day.
7/20 Moon Day: The anniversary of the day Apollo 11 landed on the moon.
7/21 – 24: International Comic-Con held in San Diego
7/22 Pi Approximation Day: The fraction 22/7 is a common approximation of Pi, as it has a value of 3.14 hence this secondary holiday.
7/26 SysAdmin Appreciation Day: Celebrated on the last Friday in July and created to show appreciation for the hard work done by system administrators.
7/27 Gary Gygax's birthday
7/29 Don't Be a Dick Day: Started by Wil Wheaton on his birthday, this is a day to be honest, kind, honorable and awesome. Also, the anniversary of the National Aeronautics and Space Act which gave birth to NASA.

August

National Inventors Month
8/5 International Beer Day: Celebrated on the first Friday in August every year by, you guessed it, drinking beer with friends.
8/12 IBM/PC Day: On this day in 1981, IBM introduced the Model 5150 personal computer.
8/19 Gene Roddenberry's birthday
8/20 H.P. Lovecraft's birthday
8/22 Ray Bradbury's birthday
8/24 Pluto Isn't a Planet Day: Commemorates the day in 2006 when Pluto was downgraded from "planet" status to "dwarf planet."
8/27 International Cosplay Day: Celebrated on the last weekend in August.
8/29 (Terminator) Judgement Day: Although it was brought online on Aug. 4th, 1997, Skynet did not become self-aware until Aug.29th.

September

9/7 Google Commemoration Day: While the domain was registered on Sept.4th, it is the 7th that has become the default day to appreciate the ubiquitous search engine.
9/8 International Literacy Day: Because reading is awesome.
9/12 Programmer Day: The day to appreciate a programmer falls on the 256th day each year, as 256 is the number of distinct values represented by an 8-bit byte.
9/17 Optimus Prime Day: Transformers original release date was Sept.17th, 1984. Also, World Emoji Day.
9/19 Talk Like a Pirate Day: Aaaarrrgh, matey! Also, the anniversary of the first emoticon.
9/20 Software Freedom Day: Held on the third Saturday in September to increase awareness of the virtues and uses of free software. Also, for Firefly fans, Unification Day according to Nathan Fillion.
9/22 Hobbit Day: Both Frodo and Bilbo were born on Sept. 22nd.
9/26 Batman Day: Commemorates the first time Bruce Wayne put on his bat-cape and cowl. There is, however, some debate about whether the date should be June 26th (the day Wayne's parents were killed).
9/28 Ask a Stupid Question Day: You know there's some half dumbass question you've really been meaning to get an answer to... Well, today is the day.

October

10/03 Techie Appreciation Day: A day to show some love for the "techies." Also, Virus Appreciation Day which is a good time to maybe run a scan.
10/05 Neil deGrasse Tyson's birthday
10/7-13 National Metric Week: A full week of metric fun culminating on 10/10 (as the metric system is based on powers of 10).
10/8-9 Alternative Press Expo in San Jose
10/11 Ada Lovelace Day: An international day of celebration held annually on the second Tuesday in October to help people learn about the roles of women in STEM fields.
10/12 The Hitchhiker's Guide To the Galaxy was first published on this day in 1979
10/16 Steve Jobs Day
10/21 Back to the Future Day: In 2015 we celebrated the day that Marty journeys into the future to save his children. Also, Alfred Nobel's birthday.
10/23 Mole Day: An unofficial holiday for chemists based on Avogadro's Number 6.02×10²³ and intended to foster interest in chemistry.

November

11/5 Guy Fawkes Day: Remember, remember the fifth of November. Also, Worldwide Dungeons & Dragons Day.
11/7 Marie Curie's birthday
11/9 Pi Celebration Day (Also, Carl Sagan's birthday): Yet another day to celebrate Pi, this time on the 314th day of the year.
11/10 World Science Day for Peace and Development: A day to renew international commitment to the responsible use of science to benefit society.
11/23 Fibonacci Day: Fibonacci's sequence of 1,1,2,3 which provides the date for this holiday. Also, the day that World of Warcraft was first released in 2004.
11/24 Evolution Day: Commemorates the publication of Darwin's On the Origin of Species.
11/25 Update Your Parents Browser Day: May no longer be in celebration; may need to be brought back into celebration. Also, Buy Nothing Day.
11/30 Computer Security Day: A reminder to protect your computer and information.

December

12/2 Kill a Bug Day: Reader Ed G. alerted us to this holiday, initiated by an employee at a Dutch bank who encourages colleagues to use this day to fix program issues.
12/5 Day of the Ninja: A day to dress like a ninja and "engage in ninja-related activities."
12/10 Ada Lovelace's birthday
12/11 International Shareware Day: Thanks programmers! Thanks free software trials!
12/15 National Cat Herders Day: A day to recognize the frustration of "trying to manage the unmanageable."
12/23 Festivus: Time for feats of strength!
12/28 Stan Lee's birthday, Linus Toravald's birthday
12/30 Andromeda Galaxy: On this day in 1924, Edwin Hubble revealed that the Milky Way was just one of many galaxies in the universe and that the spiral nebula Andromeda was also a galaxy.