Sonic Jam
"Sonic Jam" is a compilation which contains the four main "Sonic the Hedgehog" games released on the Sega Genesis: "Sonic the Hedgehog", "Sonic the Hedgehog 2", "Sonic the Hedgehog 3", and "Sonic & Knuckles". Unlike future "Sonic" collections, "Sonic Jam" does not use a Genesis emulator; the games are proper ports, and all are nearly identical to the original Sega Genesis releases, with the exception of minor bug fixes. "Sonic Jam" emulates "Sonic & Knuckles" "lock-on technology"—a special feature that allows the player to merge elements of "Sonic & Knuckles" into previous games, resulting in changes to the level design as well as the choice to play as Knuckles the Echidna in "Sonic the Hedgehog 2" and Tails in "Sonic & Knuckles".
History of Sega
In spite of the launch of the PlayStation and the Saturn, sales of 16-bit hardware/software continued to account for 64% of the video game market in 1995. Sega underestimated the continued popularity of the Genesis, and did not have the inventory to meet demand for the product. Sega was able to capture 43% of the dollar share of the U.S. video game market and sell more than 2 million Genesis units in 1995, but Kalinske estimated that "we could have sold another 300,000 Genesis systems in the November/December timeframe." Nakayama's decision to focus on the Saturn over the Genesis, based on the systems' relative performance in Japan, has been cited as the major contributing factor in this miscalculation. According to Sega Technical Institute head Roger Hector, after Sony's release of the PlayStation, the atmosphere at Sega became political, with "lots of finger-pointing".