Short answers, pulled from the story.
The Dungeons & Dragons Starter Set was first released in 1994 by TSR Inc. This product called First Quest included an example of play on a CD and served as an introduction to Advanced Dungeons & Dragons.
The Dungeons & Dragons Starter Set released on the 15th of July 2014 included a 32-page rulebook for playing characters level 1 and 5, a 64-page adventure module called Lost Mine of Phandelver, five pre-generated characters, and dice. This set was set in and around the village of Phandalin in the Forgotten Realms.
The Stranger Things Dungeons & Dragons Roleplaying Game Starter Set was released on the 1st of May 2019. This box set includes a Stranger Things themed adventure called Hunt for the Thessalhydra, pre-generated character sheets inspired by the show, a set of dice, and two exclusive miniatures of the Demogorgon.
The Dungeons & Dragons Essentials Kit released on the 3rd of September 2019 contains a 64-page rulebook with new rules on creating characters, a new adventure titled Dragon of Icespire Peak, dice, character sheets, and 81 cards describing game mechanics. It also includes a code that unlocks the Essentials Kit Bundle on D&D Beyond at no extra cost.
The Starter Set Dragons of Stormwreck Isle was released on the 31st of July 2022. This starter set includes five pre-generated character sheets, an introductory rulebook, an adventure module, dice, digital tools, and short onboarding videos which explain the fundamentals of Dungeons & Dragons.
The new starter set Heroes of the Borderlands is scheduled for release in September 2025 as part of the 2024 revision to the 5th Edition ruleset. It is inspired by the original The Keep on the Borderlands adventure and will include three booklets, dice, eighteen maps, a combat tracker, over 200 game cards, and over 200 tokens.