= Macintosh
{c}
The \b[Macintosh] is a family of <computers> made by Apple. Its early machines provide a concrete example of integrating a processor, <computer memory>, a display and pointing-device input into an interactive system. The original 128K model and its 512K successor combined a built-in screen with keyboard and mouse connections; the service manual distinguishes their memory capacities.<Macintosh Service Source by Apple Computer>[Basics, Overview; Specifications, Memory and I/O Devices]{ref}
The early display contained $512\times342$ <pixels>. To model a monochrome <framebuffer> with one <bit> per <pixel>, the minimum packed image storage is
$$
512\times342=175104\ \text{bits}
=21888\ \text{bytes}.
$$
That is $21.375\times1024$ <bytes>, before any additional image buffers or program data. This is an original storage calculation using the documented display dimensions, rather than a claim about a particular program's memory allocation.<Macintosh Service Source by Apple Computer>[Specifications, Sound and Video p. 6, 512×342 bit-mapped display; one-bit depth also listed at https://support.apple.com/en-om/112190]{ref}
The example connects a visible <pixel> to an addressable representation in <computer memory>. Drawing a black line requires changing selected <bits>; a <graphical user interface> uses such drawing operations to represent controls and documents. Raising either display dimension increases storage even if the processor and the number of values represented per <pixel> remain unchanged.
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