Gary Oak, also known as Blue Oak and Gary Motherfucking Oak is a video game reference used to undermine any sort of achievement. It is based on the rival character from Nintendo Gameboy's Pokemon Red/Blue, who was always one-step ahead of the player's character. Similar to the Chuck Norris facts, the fictional Pokémon character is typically mentioned to remind someone that you are not the best because Gary is the one. His supreme dominance has been also referred to as his "girth." This stems from a demotivational poster depicting an adult roleplay chat in which someone tried to put "Gary Oak" on ignore. "Gary" said "you can't ignore my girth."
On February 27th, 1996, Pokémon Red and Pokémon Green were released in Japan. In the game, Gary Oak or "Blue Oak" as he is known in the games, is the main player's rival. He appears at the most inopportune moments: right after a series of difficult battles, or at the end of a very long level (clip below).
The Gary Oak meme began as a copypasta, which was rumored to have been first posted on /v/ on November 16th, 2001. However, the earliest available version of the copypasta come from a post by an anonymous 4chan user on the /b/  image board from November 23rd, 2007 (shown below).
I'm Gary MOTHERFUCKING Oak, /b/
And girls want to fuck me. Let it piss you off as much as you want, but you know it's completely true. That girl you like who is kinda cute in a weird way, but is totally sweet and you have the biggest crush on? The one who keeps going back to guys who treat her wrong for reasons you don't understand? The one who calls you up at 1 am to cry about how her boyfriend hasn't called her in 3 days, and no matter how long you listen to her, she'll never think of you as anything other than asexual? The one who will curl up next to you on the couch, hug you close, kiss you on the cheek, and never let you fucking touch her beyond that?
Yeah, I'm fucking her. I'm Gary MOTHERFUCKING Oak.
The hot girl who won't even look at you when you nod at them and smile? The one who laughs when you trip in the hallway and drop your stuff? The one who comes up and coyly asks for your help with her homework, and then pretends you don't exist once you finish?
Yeah, I'm fucking her too, even harder, because I'm Gary MOTHERFUCKING Oak.
The geeky girl you think might be enough like you that you have a chance with her? She plays Warcraft on your server, and watches anime, and reads comics? She's so incredible and you just love her so much but you still haven't worked up the courage to tell her how you feel about her?
Guess who just sucked me off and told me they'll always love me?
-- Gary MOTHERFUCKING Oak. Smell ya later
On February 17th, 2008, Urban Dictionary  user the dan defined "Gary Oak" as "Gary oak is a pokemon based forced meme originally from 4chan's /v/ board, but quickly spread from there. Gary (MOTHERFUCKING) Oak is the guy who shows up at the worst possible time, have what you want, tell you to smell him later, and generally be a gigantic douchebag. he is also a character in the pokemon series." The post received more than 1,100 upvotes in less than 14 years (shown below).
In 2008, the character inspired a number of YouTube videos. For example, in June 2008 a video of Gary Oak singing the song "My United States of Whatever" was uploaded to the site (clip below, left). The video has since been deleted.
On March 28th, 2014, YouTuber JustFunnyShit uploaded the video "Gary Oak the Pokemon F***er! (FUNNY CENSORED PARODY)" in which several clips of Oak from the Pokémon anime are edited to include explicit language. The post received more than 26,000 views in less than seven years (shown below).
Ever since the launch of /vp/, formerly /tr/, 4chan's Pokemon board, in July 2010, there has been a major increase in the number of Gary Oak threads, mainly in the form of Garybombing, the act of spamming terrible and pointless threads with images of Gary Oak. Due to the dubious quality of said board, the number of these spammed threads has remained high.
It's 1997 and you're downloading Pokémon porn on your 56k modem. Oh boy, this zip file full of Misty nudes only has 10 minutes left. You've been waiting six hours for this. When the file gets to 99.9%, you start unzipping your pants and are getting ready for the fap of your life. At that moment, guess who picks up the phone and disconnects you? GARY MOTHERFUCKING OAK.
You have just been rewarded with your Masters Degree in Cancer Research. In ten minutes you are going to have an interview to get the job of a lifetime with a six digit salary. You'll be able to pay off your student loans no problem. You flip on the TV right before you leave and what do you see? GARY MOTHERFUCKING OAK has just found the cure for cancer.
You have just fended off a shark, you are bloody and tired but you can climb onto the boat when who shows up to stomp your fingers? GARY MOTHERFUCKING OAK.
You're walking home at night and a mugger attacks you with a knife. You are able to drive him off using years of karate lessons, still sustaining some deep knife wounds. Guess who shows up and asks you for your wallet with a baseball bat? Gary MOTHERFUCKING OAK, that's who.
Congratulations, You have finally beaten Gary Oak and have no healing items left over. You head over to the Pokemon center and then the PokeMart, guess who blocks the entrance to the Pokemart. GARY MOTHERFUCKING OAK That's Right, Gary Oak is just that Epic.
Gary Oak just finished owning your ass with kung-fu. He's walking to the hospital to recover from the wounds he got. He's tired. He crashes into a mirror, and ends up in a coma. Why? Because not even GARY MOTHERFUCKING OAK is safe from GARY MOTHERFUCKING OAK.