Loading Screens are specific screens that are displayed while a game is loading resources so that the player has something to distract them while the game loads. Loading Screens can be images, text or even mini-games and sometimes a combination of all three.
The loading screen warns players that their device is still working and sometimes provides alternative entertainment to deal with data loading. Boot screens are becoming more common as consoles move from chip-based memory like cartridges to optical solutions like CD-ROMs.
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However, this does not mean that the boot time starts with the CD-ROM; Many early computer games, apart from a few cartridge-based games, had incredible loading times.
While the capacity and cost of optical media is much cheaper than chip-based memory, optical media suffers from much slower read speeds that require a lag to load RAM resources so that gaming is not interrupted at critical times.
The increase in resources (today's games are typically several gigabytes in size) compared to device speed also plays a role, as the maximum transfer speed achievable with mechanical storage devices such as optical drives and hard drives is a limiting factor. Since the boot screen is intermittent, efforts are being made to make it as fun or enjoyable as possible.