| | | | Prologue |
| | James D. | Halliday | The Creator of OASIS. Deceased. aka: Jim. |
| | | | OASIS - A Virtual Reality Massively Multiplayer Online Game. |
| | | | OASIS - Ontologically Anthropocentric Sensory Immersive Simulation. |
| | | | Adventure - James Donovan Halliday's First Video Game. |
| | Warren | Robinett | The Creator of Adventure. |
| | Anorak | | Jim's famous avatar. |
| | Winona | Ryder | An American actress. |
| | Christian | Slater | An American actor. |
| | | | Level One |
| 1 | Loretta | Watts | Wade's mother. |
| | Wade | Owen-Watts | Protagonist and Narrator. |
| | Alice | | Wade's aunt. Loretta's sister. |
| | Rick | | Alice's boyfriend. |
| | Mr. | Miller | One of Wade's neighbors. |
| | Mrs. | Gilmore | Wade's 70 year-old neighbor. Wade's friend. aka: Mrs. G. |
| 2 | Parzival | | Wade's Oasis avatar name. |
| | Todd13 | | Wade's classmate in Algebra II. |
| | | | Ludus - A planet where OASIS Public School located. A No-PvP Zone. |
| | | | Incipio - A planet at Sector One where new Avatars spawned. |
| | | | Gunter - A player in Oasis. |
| | | | Sixers - IOI's Egg Hunters. |
| | Art3mis | | Owner of the blog Arty's Missive. Wade's Gunter Friend. aka: Claire. |
| | | | IOI - Innovative Online Industries. |
| | Aech | | Wade's online best friend. |
| 3 | I-r0k | | A Gunter at The Basement's Chatroom. |
| | | | Basement - Aech's chat room. |
| 4 | Mr. | Avenovich | Wade's teacher in World History. |
| 5 | Mr. | Ciders | Wade's advanced Oasis teacher. |
| | Ogden | Morrow | Jim's best friend and business partner. |
| | | | MMOs - Massively Multiplayer Online Games. |
| | | | GGS - Gregarious Simulation System. |
| 6 | Ms. | Rank | Wade's Latin teacher. |
| | | | The Limerick - James Halliday's Egg Hunt Clue. |
| | Gary | Gygax | One of the Creators of Dungeon & Dragons. |
| 8 | Acererak | | A monster at the Tomb of Horror. |
| | | | OST - Oasis Server Time. |
| 9 | Howard | Jones | An 80s poet. |
| 11 | Matthew | Broderick | An American actor. |
| | David | Lightman | Matthew Broderick's character in the movie "Wargames". |
| | Howie | | A Kid from the movie "Wargames". |
| 12 | Edgar | Nash | A Gunter Expert. |
| | Kira | Morrow | Ogden Morrow's high school sweetheart. |
| | Ally | Sheedy | An American actress. |
| 13 | Daito | | A Gunter who came in 4th at the Leaderboard. |
| | Shoto | | A Gunter who came in 4th at the Leaderboard. Daito's best friend. |
| | Nolan | Sorrento | The Sixers's Infamous Leader. |
| | | | Level Two |
| 16 | Bryce | Lynch | Wade's bogus Identity. |
| 17 | Martha | Plimpton | An American singer. |
| | Sean | Astin | An American actor. |
| | John | Draper | A 70s Hacker. aka: Captain Crunch. |
| 18 | Og | | Ogden Morrow's famous avatar. |
| | | | Neonoir - One of the largest and oldest planets in Oasis. |
| | Connor | Macleod | A fictotinal character from the movie "Highlander". |
| 20 | | | ACHD - Anomatically Correct Haptic Doll. |
| | Max | | An AI portrayed by the actor Matt Frewer. Wade's friend in Oasis. |
| | Erin | Gray | An actress. |
| | | | Falco - Wade's planet in Oasis. |
| | Shin | Hayata | Protagonist in "Ultraman". |
| 22 | William | Higinbotham | The Inventor of video game "Tennis for Two". |
| | Toru | Iwatani | A Japanese game designer. |
| | | | Frobozz - Detailed as the re-creation of the game "Zork". |
| 23 | | | Xyzzy Cluster - Tribute to Oasis's Earliest Ancestor. |
| 26 | Philip | K. Denton | James Halliday's Favorite Authors. |
| | | | Axrenox - The Cyberpunk-themed planet in Oasis. |
| | Eldon | Tyrell | Tyrell's corporation founder. |
| 27 | Syrinx | | A planet in Oasis located in Sector 21. |
| | | | Level Three |
| 28 | Joe | Dante | The Director of the movie "Explorers". |
| | Michael | Wilson | IOI's credit and collections Officer. |
| 29 | Nancy | | An IOI's Indenturement Counselor. |
| | | | IOI-N - The IOI's 24 Hour News Network. |
| | Hotcock007 | | Wade's first customer as an IOI Technical Support aide. |
| | Henry | Swanson | Aech's bogus identity in IOI. |
| 31 | Harry | Tuttle | Wade's IOI employeee identity. |
| 33 | Helen | Harris | Aech's true identity. |
| | Marie | Harris | Aech's mother. |
| 37 | Dave | Theurer | The Creator of Tempest. |
| 38 | Professor | Falken | The Creator of WOPR. |
