Bill is a Pokémon researcher regarded as an expert in many fields, best known for inventing the original Pokémon Storage System and the Time Capsule. In Pokémon Red, Blue and Yellow the player finds him at the Sea Cottage on Cerulean Cape, north of Cerulean City, after a teleportation experiment has merged him with a Pokémon; FireRed and LeafGreen show that Pokémon as a Clefairy. Once the player runs his separation program, the PC menu entry "Someone's PC" becomes "Bill's PC", and he gives the player the S.S. Ticket for the S.S. Anne as thanks.
Bill calls himself a Poké Maniac, and his favorite Pokémon are Eevee and its evolutions. In Gold, Silver, Crystal, HeartGold and SoulSilver he is visiting his family in his hometown of Goldenrod City, gets the Time Capsule running in Ecruteak City and gives the player an Eevee. FireRed and LeafGreen also take the player with him to the Sevii Islands, where he introduces his friend Celio.
Bill was on cards from the start: the Base Set (1999) Bill is a Common Trainer that simply draws two cards, reprinted in Base Set 2 and Legendary Collection. Neo Genesis (2000) added Bill's Teleporter and Neo Destiny added Mail from Bill. When the Supporter card type arrived with Expedition Base Set (2002), Bill's Maintenance was among the first Supporters, and it was reprinted in FireRed & LeafGreen, Crystal Guardians and POP Series 5, every time with Ken Sugimori art.
HeartGold & SoulSilver (2010) printed a Bill Supporter, and Celestial Storm (2018) brought Bill's Maintenance back as an Uncommon and a full art Ultra Rare by Sanosuke Sakuma. Team Up (2019) introduced Bill's Analysis by Naoki Saito, reprinted in Hidden Fates later that year, and the Kanto-themed 151 set (2023) added Bill's Transfer by GIDORA as an Uncommon and an Ultra Rare.
No Pokémon card has been named as Bill's; every card with his name is a Trainer. Ken Sugimori illustrated his main-set cards from the Base Set through HeartGold & SoulSilver, with Bill's Teleporter (Keiji Kinebuchi) the one exception. His only Ultra Rares are the Celestial Storm Bill's Maintenance and the 151 Bill's Transfer.
A Neo Genesis Trainer named for the teleporter at his Sea Cottage, illustrated by Keiji Kinebuchi.
One of the first Supporter cards, from the set that introduced the card type in 2002.
A full art Ultra Rare of Bill's Maintenance by Sanosuke Sakuma (2018).
The Hidden Fates reprint of the Team Up Supporter, illustrated by Naoki Saito.
The Ultra Rare of his newest Supporter, from the Kanto-themed 151 set, by GIDORA.
Bill, a Common Trainer in the Base Set (1999) that draws two cards. It was reprinted in Base Set 2 and Legendary Collection.
The original Pokémon Storage System, the PC system that holds Pokémon a Trainer is not carrying, and the Time Capsule.
No. Every card with his name is a Trainer card, such as Bill, Bill's Maintenance, Bill's Analysis and Bill's Transfer.
In Red, Blue and Yellow the storage entry reads "Someone's PC" until the player meets Bill at the Sea Cottage and helps him undo his teleporter accident; after that it becomes "Bill's PC".

TRAINER
17 Trainer cards · 0 partner Pokémon
Bill is the Kanto researcher who invented the Pokémon Storage System, first met at his Sea Cottage after a teleportation experiment leaves him fused with a Pokémon. He has been on Trainer cards since the 1999 Base Set, from Bill's Teleporter and Bill's Maintenance to 151's Bill's Transfer.