Try! Let's have a fight!

 Hey how about some pointless trivia about Pokémon? Yes, again. Shh.

The actual phrase used in the games for when a wild Pokémon encounter starts is "A wild [Pokémon name] appeared!" (emphasis mine), or simply "Wild [Pokémon name] appeared!" in the Gen 1 games. On the internet, it's often misquoted in jokes and memes as "A wild X appears" or "A wild X has appeared".

Similarly, jokes and memes often misuse the phrases "It's super effective!" and "It's not very effective..." In the games, these messages indicate when a move does more or less damage thanks to a type advantage. It doesn't apply to moves that don't inflict any damage to begin with, such as Hypnosis (which simply has a chance of causing the target to fall asleep, or become drowsy in Pokémon Legends Arceus).

Detractors of the anime or of Satoshi/Ash Ketchum will often claim that Ash didn't really win his first two Gym Badges, and that he only got them out of pity. The fact the show itself has made this joke does not help matters, but the reality is far from the case. Ash lost his first match with Brock, but during the second match he had Brock on the ropes and was about to win when Pikachu's electricity accidentally set off the sprinklers, weakening Brock's Onix (due to Onix being a Rock/Ground type making it doubly weak to Water), which caused Brock's siblings to guilt Ash into forfeiting. It was Ash who felt sorry for Brock, not the other way round. As for Misty, she blatantly cheated in her match by coddling Pikachu before the fight, making him less likely to want to battle her - in other words, tampering with the opponent's Pokémon, which is considered a foul in many official battles and tournaments. And even then, the match was interrupted by Team Rocket attacking the Gym, after which Misty's sisters awarded Ash the Cascade Badge as thanks for saving their Gym. So while Ash technically didn't win either of his matches against them, to say he got their Badges due to pity is both incorrect and rather unfair.

A common misconception is that Rock is immune to Electric. It actually takes neutral damage. The reason many people think this is that the most common Rock types in Gen 1 - that is, the Geodude line, the Rhyhorn line, and Onix - are all part Ground, which is immune to Electric. Note that the other two Rock types in Gen 1, namely the two Fossil Pokémon, are not immune to Electric, and in fact are weak to it due to both being part Water type. The writers of the anime made this same mistake, with one episode showing a Kabutops shrugging off Pikachu's electric attacks like it was nothing, when it should have been weak to them.The series got its first pure Rock-type Pokémon when Sudowoodo debuted in Gen 2.
On a similar note, Ghost is not weak to Psychic. Again, the reason people think this is that in Gen 1, the only Ghost types are the Gastly line, which are also part Poison, and Poison is weak to Psychic. The series wouldn't get a pure Ghost type until Misdreavus debuted in Gen 2.

It's often claimed that if a Charmander (or its evolutions) has its tail flame extinguished, the Pokémon will die. This is a misconception that arises from an episode of the anime in which Brock mentions that if a Charmander's tail flame goes out, it dies, while the episode in question had a sick and dying Charmander in heavy rain whose tail flame was about to go out. It's actually the opposite - the tail flame is an indicator of the Charmander's health and life, not the source of it. What Brock meant (and what is actually the case) is that when a Charmander dies, its tail flame goes out - as in, its tail flame goes out because it dies, not the other way round. The Charmander in the episode was merely sick from being in the rain (as well as starving and weak), it wasn't dying due to the rain almost putting out its tail flame. In fact, we've seen Charmander and its evolutions being completely submerged in water many times in the series, with their tail flames continuing to burn brightly even so.

The common explanation for why Psychic is weak to Bug, Dark and Ghost is that those types represent common fears, and fear can affect the mind.

The name of the Dark type is a bit of a misnomer in English, with most Dark moves actually being based more around trickery, deceit, or just plain not playing fair, as opposed to actual darkness-based attacks, which often tend to be Ghost-type moves instead. The explanation for this is that in Japanese, Dark type is known as Aku type, which literally means Evil type, hence why Dark-type attacks are less focussed on darkness and more on just being mean and unfair. However, the Dark-type Z-Move, Black Hole Eclipse, is a darkness-based attack, as is the Dark-type Max Move, Max Darkness (Dai Dark in Japanese). Gigantamax Grimmsnarl also has a unique Dark-type G-Max Move, G-Max Snooze (Kyodai Suima, literally Giganta Sleepiness), which is also a darkness-based move with a 50% chance of causing the target to become drowsy, similar to Yawn. On the other hand, Gigantamax Single Strike Urshifu's G-Max Move, G-Max One Blow (Kyodai Ichigeki), leans more towards the trickery aspect, as it always hits even if the target is protected by a protection move.

The only two characters in the anime dub to have a confirmed surname are Ash Ketchum and Tracey Sketchit. Misty is often referred to as Misty Waterflower (a result of people confusing her sisters' title for their surname) or Misty Williams (which is just purely made up by the fans). Brock's English voice actor, Eric Stuart, has given Brock's full name as Brock Harrison, but that's just something he made up and not actually canon. Sabrina is occasionally given the full name Sabrina d'Avalon, but again, that's something that was made up by the fans and not canon.

Misty is often believed to be 12 years old in the anime, but her actual canon age is 10, same as Ash. However, she is canonically 12 in the manga Pocket Monster: Dengeki Pikachu (released in English as The Electric Tale of Pikachu), which loosely adapts the events of the anime.

It's often said that the Kanto region in the games is based on the real-life Kantō region of Japan. In fact, it's not a one-to-one depiction - the Kanto of the games is both based on real-life Kantō and the east side of Chūbu, which neighbours it. Similarly, Johto is based on both the Kansai region and the west side of Chūbu.

On a similar note, people often claim that Unova is based on the United States of America in general, when it's actually specifically based on the New York metropolitan area. Several locations in Unova are directly based on locations in New York, including Castelia City (Hiun City in Japan, heavily based on Lower Manhattan and having its own equivalents of Brooklyn Bridge (Skyarrow Bridge) and Times Square) and Nimbasa City (Raimon City in Japan, host of the Pokémon Musical which is clearly inspired by Broadway theatre and with locations based on Madison Square Garden and Grand Central Terminal). The Pokémon native to Unova take inspiration from things all around the world, reflecting the "melting pot" nature of New York, rather than being based on stereotypically American things like cowboys, baseball, etc. (though a few are, such as Braviary). People also often claim that Virbank City (Tachiwaki City) is based on Los Angeles because its name is similar to Burbank and it's close to the Pokéstar Studios (which is called Pokéwood in Japan), when its heavy pollution, "tough" aesthetic, oil refineries and location relative to the rest of Unova make it clear it's actually based on New Jersey.

A few Pokémon names are commonly misspelled. For instance, Phanpy is very commonly misspelled and mispronounced as Phanphy. Gastly is often misspelled as Ghastly, and Ninetales often gets misspelled as Ninetails. Bonsly's name was mispronounced in the English dub of the anime as Bon-slee, when the intended pronunciation was Bons-lie, being a combination of bonsai, sly, and lie. The pronunciation of Arceus's name was deliberately changed in the English dub of the anime from Ar-say-oos (the Japanese pronunciation) to Ark-ee-us, because the translators thought the original name sounded too much like "arse" (the British equivalent of "ass").

Many player characters and rivals of the games did not have canon names for a long time, despite what many fans think - they were unnamed in-game, with their names being chosen by the player. The game Pokémon Masters EX canonised a lot of the names, including canonising the Johto rival's name as Silver, which was his most common fan nickname. Most other names came from the characters' anime counterparts, though a few, such as Gen III's Brendan and May and Gen VI's Calem and Serena, were given in the games (as whichever character you don't choose to play as functions as your rival, and in that case their name is revealed). The names Red and Blue (or Red and Green in Japan) for the player character and rival respectively of the Gen I games were canonised in Gen II, where Red appears as the final challenge of the game and Blue appears as the Viridian City Gym Leader. Before this, their "canon" names were Satoshi/Ash and Shigeru/Gary, the names of their counterparts in the anime.

It's often claimed that Pikachu is based on a type of lagomorph called a pika. The name "Pikachu" comes from the Japanese onomatopoeia "pikapika" meaning sparkling, and "chuchu" being the sound of a mouse squeaking. Pikachu is known as the Mouse Pokémon, and the designers of Pokémon have confirmed that its design is based on squirrels, though its resemblance to any real-life animal is loose at best.

In the early days of the series, both games and anime, real-world (non-Pokémon) animals seemed to exist in the Pokémon world. Raichu's Pokédex entry in FireRed infamously mentions it having enough electric power to cause "an Indian elephant" to faint (which is also mentioned in its Sun Pokédex entry), and real-life birds and fish were occasionally seen in early episodes of the anime. These seem to have been phased out as the series continued, with Pokémon now being the only type of creature in the world.

It's a common misconception that the player was originally going to be able to choose between a male and female protagonist in the original Gen 1 games, due to official promotional artwork depicting main character Red, his rival Green/Blue, and an unnamed girl facing off against each other. In reality, there were never any such plans, and the unnamed girl in the artwork was created specifically for the picture, in order to depict the whole starter trio. (This girl may or may not have inspired the character Leaf, the female protagonist in the remakes FireRed and LeafGreen).

People often quote Professor Oak as asking "Are you a boy or a girl?" in jokes and memes, but as said above, there were no gender options in the Gen 1 games. He does ask the player their gender in the remakes, but what he actually says is "Are you a boy? Or are you a girl?"

People will often (usually as part of a joke about the series) refer to the protagonists of the games in general as ten-year-olds. In fact, not a single one of the game protagonists is canonically ten. Of the ones who have confirmed ages, Red and the Alola protagonists are both 11 at the time of their respective games, and the Black/White protagonists are 14 at the time of their game. The Legends: Arceus protagonists are assumed in-universe to be "15 or so", though their exact age is never stated. On a related note, there is no rule in the games that you have to be ten years old to be a Trainer, or that all Trainers start at age ten. In fact, you can disprove this just by playing the games - there are many Youngster and Preschooler Trainers in the games who are obviously much younger than ten. What you do have to be a certain age for is to travel - most young/child Trainers don't venture too far from their home towns and cities, and in Alola it's explicitly forbidden for anyone under 11 to take the Island Trials. And even then, it's shown that Trainers younger than 10 can become top-level Trainers - case in point being Poppy in Scarlet/Violet, who's nine years old and a member of the Paldea Elite Four.

Not everyone gets their starter Pokémon from a lab in the games or in the anime. The protagonists usually do, but many NPCs in the games mention getting their first Pokémon from a friend or a family member.

Not everyone in the Pokémon game universe has a Pokédex. The protagonists are a special case, along with a select few other Trainers. The confusion here is understandable, since in the anime Pokédexes appear to be much more common.

It's often believed that in the anime, Gary's starter was Eevee, given that it was the only Pokémon he ever used against Ash for a while, and the rival's starter in the anime-based Pokémon Yellow Version is an Eevee. The Johto League tournament reveals that Gary's starter was actually Squirtle, which he uses as a Blastoise in his match against Ash.

The Gen 1 rival Blue has a reputation for being a huge jerk, to the point it's common for players to give him an insulting name when prompted by the game to name him. In fact, while he is very cocky and arrogant, he's also very helpful - his dialogue often contains hints on what to do or where to go next, albeit delivered in a rather condescending manner, and later on in the game he actually becomes downright complimentary, if still very arrogant. People who think this are most likely confusing him with Silver, the Gen II rival, who is a lot more dickish and hostile to the player character, though even he eventually mellows out somewhat. Blue also has a reputation for popping out of nowhere after a big fight or other event and challenging you to a battle while your Pokémon are tired. In fact, he only does this once, in Silph Co. Every other battle with him is optional, has enough forewarning for you to prepare, or happens after you should have already visited the local Pokémon Center. Again, this is another conflation with Silver, who does do this kind of thing very often.

It's a common belief that the anime started the trend of Pokémon communicating by saying their names, but this is false. Pokémon have been saying their names to communicate right from the very beginning. People often forget that the Gen 1 games were hampered by the limitations of technology at the time, and even then, you can hear that many Pokémon cries sound very similar to their names (their Japanese names, in particular - one example being Clefairy, whose cry sounds a lot like its Japanese name, Pippi). As well, there are Pokémon NPCs in the Gen 1 games, and if you talk to them, they do say their names. The problem is a lot of them weren't translated, so for example, if you talked to a Jigglypuff NPC, it would say "Pu-pu-ri!" because its Japanese name is Purin. And then there's Mewtwo, who exclaims "Mew!" when talked to and challenged.
On the other side of the coin, not all Pokémon say their names even in the anime. Many more do in the English dub than in the Japanese, but in many cases, the Japanese cry was retained in both versions. The rule seems to be that smaller and cuter or more humanoid Pokémon say their names or parts of their names, while more animalistic or bestial Pokémon make more animal-like growls, chirps, roars, etc. which often do still subtly incorporate their (usually Japanese) names - for example, Charizard's roar sounds vaguely like its Japanese name, Lizardon, while Onix has a deep, guttural roar similar to its Japanese name, Iwark.
And then there are some Pokémon that just make random sounds. Krabby and Kingler both say what sounds like "cookie cookie", Staryu makes a deep "HYAAH" sound, Surskit (or at least Viola's Surskit in X&Y) speaks entirely in a short "a" syllable, Lapras has a high-pitched "whine" that sounds nothing like its name, etc. Occasionally it even changes - Electabuzz started out making a comical gurgling babble that sounded like it was being electrocuted (in both Japanese and English) but switched to using its name from Advanced Generation onwards, while the first time Akuziking/Guzzlord appeared in the anime, it started out speaking normally (using "ki" and "ji/zi" syllables), but in its second appearance, it simply screams "AAAAAAAAAA" with an amusingly human-sounding voice.

Pokémon Tower in Lavender Town and Pokémon Mansion on Cinnabar Island are often erroneously referred to as Lavender Tower and Cinnabar Mansion respectively. Also, the Lavender Town theme doesn't play inside Pokémon Tower (a common mistake in creepypastas) - it has its own theme.

It's often claimed that in the Japanese version of the first movie, Mew's speech near the end of the movie is a lot harsher, with it saying that clones are inferior and should perish. This is most likely the result of mistranslations - while Mew's speech is slightly different in Japanese, it's not that much different. All it says is that, whenever clones and originals fight, the originals will always win.