Charlie often exhibits difficulty reading and writing, and is often accused of being illiterate or dyslexic by other characters. Mac even went as far as claiming "No one understands the subtleties of Charlie's retardation better than me." (The Gang Gets Held Hostage)
Charlie's literacy, or lack thereof, is never really addressed in Season One. Generally speaking, he is presented as being more intelligent than he will be in later seasons.
Season Two
Charlie writes a script for a "jihad video" that The Gang wants to use to threaten Ari Frankel, but Dennis refuses to read it, saying that it is "riddled with spelling errors," and speaks gibberish meant to sound like Arabic instead. (The Gang Goes Jihad)
Charlie was unable to read his job listed on paper after blowing up a building (The Gang Goes Jihad), so he got Mac to read it for him. The words were "Interstate" and "sanitation". (The Gang Gives Back)
Charlie wrote an incoherent script for Dennis' TV commercial: "Hello fellow American. This you should vote me. I leave power. Good. Thank you, thank you. If you vote me, I'm hot. Taxes, they'll be lower... son. The Democratic vote is the right thing to do Philadelphia, so do.". (The Gang Runs for Office)
Charlie can not read a note left by Frank: Charlie: "Okay, meet... it starts out meet... um"; Dennis: (takes note) "Meet me in the parking garage. Frank. You clearly have a learning disability, dude". (The Gang Runs for Office)
Charlie wrote a note in the vents that Frank read: "If here by now then bad place be. Trouble time for you when heat comes." (The Gang Gets Held Hostage)
Charlie misread a contract that resulted in his putting the bar at risk of being lost in a contest, misreading the word PRIZE as PRIDE. (The Gang Dances Their Asses Off)
Season Four
Charlie wrote a sign to help sell the Gang's gasoline. His sign gave prices for "UNLED'D" (with the N backwards), "PREMEM" and "DEASEL". (The Gang Solves the Gas Crisis)
For some reason, Charlie is familiar with the word "disintegrated" [4x5]. Probably, he heard it in "Law & Order".
In the "list of demands" that Charlie and Mac leave in lieu of a last will and testament, Charlie demands that "[his] ashes are to be made into a tea and dranken by every wan in bar." [4x5]
Charlie has a stalking notebook, where he keeps all the Waitress' "whereabouts". For some reason, Dee was able to read it (after she stole it) - but that's okay, because Charlie have backups for it. [4x7]
Some fans have suggested that Charlie's freakout over Pepe Silvia (Sweet Dee Has a Heart Attack) might be due to him not being able to read the word Pennsylvania. Though others point out that Mac says "Not only do all of these people exist, but they have been asking for their mail on a daily basis". Though Charlie mistaking the address for a name might be a possibility if the letters were all for different people.
Charlie was unable to write clear lyrics to his musical, and needed help from Artemis. (The Nightman Cometh)
Season Five
Kitten Mittons
When Charlie tries to argue with The Lawyer about contract law, The Lawyer remarks that not only does Charlie not know anything about the law, "It seems like you have a tenuous grasp on the English language in general." Charlie responds to this by saying "Filibuster," but cannot tell The Lawyer what that word means when The Lawyer asks Charlie to define it for him. (The Gang Exploits the Mortgage Crisis)
Charlie turned on the CLOSED sign in front of the bar every morning, because he believed it says COORS. (The Great Recession)
Charlie does not know the meaning of the word "illiteracy". Later in that same episode, Dee asks a therapist to give Charlie an intervention "because he's totally illiterate" -- Charlie denies that he can't read or write, he says he just doesn't like to. (The Gang Gives Frank an Intervention)
In a somewhat surprising moment of literacy, Charlie manages to write a perfectly formed "H" on a box he has put a hornet's nest into, even though he is writing on the side of the box facing away from him, forcing him to write backwards and upside down in relation to him. (It's also a bit striking that he knows that the word "hornet" begins with an "H".) In that same episode, however, his difficulty with language raises its head again, as he cannot understand the word "philanthropist" and ends up telling his date that he is a "full-on rapist." (The Waitress is Getting Married)
Charlie was unable to read a carnival sign in front of the Waitress that said, "SpeedPitch: HOW FAST CAN YOU THROW?" (The D.E.N.N.I.S. System)
Season Six
Charlie tries to search the Internet for the word "hockey" but insists that the keyboard has no "H" key. (Mac's Big Break)
Charlie has typed the Waitress in his mobile's memory as "Wicksox" or something. He was ashamed before Mac, so he blamed a "smart type" of his phone by saying "it tries to complete the word for you". (Deleted Scene for Mac and Charlie: White Trash)
Charlie's book, which contains all his "dreams and aspirations" (which are mostly in pictures and symbols), entitled as "Dram bach" - this should stand for "Dream book". (Charlie Kelly: King of the Rats)
Season Seven
The question that Charlie wrote for Chardee MacDennisreads as follows: "Dennis is asshole. Why Charlie hate?" (the answer being, of course, "Because Dennis is a bastard man.") Charlie denies that he wrote it, but Mac says it has to be him, because "How many illiterates are there here?" (Chardee MacDennis: The Game of Games)
Probably, it was written as something like that:
Denis is ashole. Y Charlee hat? (Becauze Denis is a bastardt man!)
Charlie misread a door marks "Brett DeLawter, A Dental Corporation" as "Brett DeLawyer, A Denial Correlation". How does he know the last word? (Pop-Pop: The Final Solution)
Charlie keeps a list of things that he regularly does for The Waitress: for instance, he watch her bike so it doesn't get stolen (and barks every "suspicious" person around like a dog), puts some vitamins in her shampoo so her hair doesn't fall out, and tests her food so it doesn't get poisoned - of course, it's all in weird paintings. For some reason, Dennis is aware about that. When Frank tries to use the list to do tasks for The Waitress that Charlie was doing, he misreads it (understandably) and does the tasks incorrectly: for example, he thinks it says that he should put rat poison in her shampoo. (Charlie and Dee Find Love)
Here's a part of Bonnie Kelly's speech from her cancer fundraiser that Charlie wrote: "Give me money. Money me. Money now. Me a money needing a lot now." (Charlie's Mom Has Cancer)
When Frank takes on Charlie as his "right-hand man" for his return to the company he founded, both Mac and Dennis state that Charlie cannot read. However, Charlie does actually prove at least somewhat competent at the job, as he is able to keep track of Frank's busy schedule, apparently writing it down in an appointment book (presumably in the same mixture of drawings and fractured phrases he has used before.) (Frank's Back in Business)
In Reynolds vs. Reynolds: The Cereal Defense, Charlie wants to know who he'll be "persecuting" (instead of prosecuting) in the trial. He immediately follows up Dee's remark on this mistake with the word "irregardless," which does not exist. Another point in the episode that demonstrates Charlie's minimal grasp of the English language is when he replaces the words "distinguished colleagues" with "distinguished collies."
Dennis: I'll read the words you wrote. "Hello fellow American. This you should vote me. I leave power. Good. Thank you, thank you. If you vote me, I'm hot. What? Taxes, they'll be lower... son. The Democratic vote is the right thing to do Philadelphia, so do." This doesn't make any sense!
Charlie: Alright... then just say whatever you want.
Charlie: Lastly, before I open the bar in the morning, I always make sure to turn on the "Coors" sign, let people know we got ice delicious Coors in the bar, you know, and then that's the last thing I do. Ol' Charlie's done a lot of work around here.
