With its roots in text-based adventures and simple shooters, computer gaming makes up an integral part of today's electronic games industry. An adaption of tic-tac-toe created in 1952 represents one of the earliest computer games, along with the heavily influential Spacewar!, a space combat game developed by MIT students on a PDP-1 mainframe computer in 1961. Personal computers brought games into the home, with manufacturers such as Atari, Texas Instruments and Commodore leading the way in the 1980s. While many early computer games required text commands to be entered via the keyboard, making text adventures and interactive fiction games popular, publishers also took advantage of the arcade game craze sweeping the nation. Ports and clones of the most recognized graphics-based games, such as Pac-Man, Frogger and Space Invaders, became top sellers on the personal computer. Increasing graphical capability, larger amounts of memory and the growing popularity of the mouse contributed to the rise of the computer gaming industry in the late 1980s and early 1990s. The mouse was especially influential in popularizing certain genres over others for the PC, as it allowed faster and more accurate movements than console controllers. Real-time strategy games and first-person shooters especially benefited from these advantages. Manufacturers also distinguished their products from console games by packaging them in larger boxes that often included extra game-related merchandise, such as badges, stickers or glasses. Computer games also popularized the idea of multiplayer gaming, especially once broadband internet became common. The first multiplayer online role-playing game, Neverwinter Nights, ran on AOL from 1991 from 1997. Other popular games followed, such as World of Warcraft, Ultima Online, StarCraft and The Sims Online. Most online games allow players to work both collectively as well as against one another in Player vs. Player or Deathmatch modes. Computer technology is currently developing and improving at a rapid pace, and computer games follow the same trends. Improved graphics, faster processing speeds and terabyte-sized memory allow games to reach new heights of realism and interactivity.