Space is a type of scarcity and is concerned with the size of things. Data shuttles across networks and into machines where it is stored ephemerally in RAM and possibly saved to permanent storage in the form of hard or solid-state-drives (HDDs, SSDs). As proponents of efficiency, we are interested in only using the space necessary to do a given task, and part of this is using the available space in the most efficient manner, and only moving data when it is prudent to do so.

Due to the high-level nature of the JavaScript language and the applications it usually builds, we rarely have to think about ephemeral RAM usage or permanent storage. However, JavaScript has gained significant ground as a legitimate language in performance-sensitive ...

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