Compressing an entire Windows folder with WinRAR sounds like an inexpensive solution to a full hard drive, until the archiving process starts deleting operating system files. Linus Tech Tips takes this questionable storage-saving idea from a Reddit post and uses it to explore how file compression works, why it became essential during the early days of personal computing, and whether it still makes sense today. What begins as a potentially disastrous experiment develops into an entertaining technical history lesson with a practical conclusion: compressing Windows isn't necessarily a bad idea, but choosing the wrong method can create serious problems.
The opening demonstration establishes the danger immediately. WinRAR successfully begins archiving Windows system files, encountering errors when it reaches files currently in use but continuing through much of the directory. More concerningly, selecting certain options allows it to delete files after compressing them, potentially leaving the operating system unusable. This is an effective illustration of why ordinary archiving software is unsuitable for managing active system files. However, the experiment stops short of documenting the full consequences of the operation, leaving viewers without a definitive demonstration of how badly Windows would be affected or whether recovery would be possible.
The explanation of storage inefficiency provides useful background for understanding why compression became important. Linus describes how traditional disk sectors could waste space when files failed to occupy an entire allocation unit, then introduces the concept of bundling smaller files together. The discussion progresses into compression algorithms that identify repeated information and replace redundant sequences with more efficient representations. Everyday analogies, including vacuum-packed food and simplified sequences of repeated colors, make these concepts approachable without demanding extensive technical knowledge. Some explanations are deliberately simplified, particularly the relationship between disk sectors, file storage, and archive containers, but they successfully establish the basic principles.
The historical discussion is particularly interesting. Early compression algorithms, including work associated with Lempel and Ziv, provide the foundation for an explanation of how developers attempted to overcome the severe storage limitations of early computers. The introduction of Stacker illustrates how software could effectively expand usable hard drive capacity by compressing data inside a virtual disk container. Linus also explains why reading compressed information could actually improve performance when hard drives were substantially slower than the processors handling decompression. These historical examples give the subject more depth than a conventional storage-management tutorial, although the rapid progression through competing formats, commercial disputes, and operating system developments leaves some details unexplored.
Modern Windows compression brings the discussion back to practical usefulness. Rather than treating the Reddit user's idea as entirely foolish, Linus identifies CompactOS, a built-in Windows 10 and 11 feature specifically designed to compress operating system files. This distinction is valuable because it demonstrates that the underlying concept is legitimate even when the original implementation is dangerous. The explanation also acknowledges the computational overhead involved in compressing and decompressing files. However, the presentation would be considerably more useful with an actual CompactOS demonstration, measured storage savings, and performance comparisons. Without those results, viewers must accept a largely qualitative assessment of whether the feature is worth enabling.
The examination of modern file formats further strengthens the argument against expecting dramatic savings from additional compression. Linus points out that documents, websites, photographs, music, and videos already employ various forms of compression, limiting how much additional space conventional tools can recover. His distinction between lossless compression, which preserves the original information, and lossy compression, which removes selected data, is especially accessible. References to JPEG, MP3, AAC, and video formats connect the technical concepts to familiar applications. Still, the broad discussion of contemporary storage economics and compression efficiency would benefit from specific measurements showing how much different categories of files can realistically shrink.
The presentation maintains a lively atmosphere through exaggerated reactions, visual comparisons, historical trivia, and Linus's characteristically sarcastic delivery. The humor generally makes the technical material easier to follow, especially when explaining concepts that could otherwise become dry or excessively complicated. Unfortunately, the extended sponsor segments are less successful. The recurring comedy sketch surrounding a coding course becomes an increasingly elaborate interruption, and its length feels disproportionate to the relatively straightforward subject. The result is an informative and entertaining exploration that occasionally prioritizes comedy and promotional material over the practical testing that would have strengthened its central argument.
Pros
- Uses a genuinely risky Windows compression experiment to introduce a practical storage-management problem and immediately establish its potential consequences.
- Explains fundamental compression principles through accessible examples of redundant data, repeated sequences, and inefficient storage allocation.
- Provides interesting historical context surrounding Lempel-Ziv algorithms, Stacker, early disk compression, and the relationship between storage speed and processing power.
- Identifies Windows CompactOS as a legitimate alternative to using conventional archiving software on essential operating system files.
- Clearly distinguishes lossless and lossy compression while connecting both concepts to familiar document, image, audio, and video formats.
- Explains why already-compressed modern files offer diminishing opportunities for additional storage savings.
- Combines approachable technical explanations, historical trivia, and humor into an engaging presentation.
Cons
- Does not fully demonstrate the consequences of deleting archived Windows system files or document the resulting operating system behavior.
- Provides no controlled CompactOS benchmarks, actual storage-saving measurements, or performance comparisons to substantiate its practical conclusions.
- Simplifies several technical and historical concepts, leaving some distinctions between disk allocation, file packaging, and compression insufficiently developed.
- Offers limited actionable guidance for viewers who might want to evaluate or safely use Windows' built-in compression capabilities.
- Extended sponsor comedy interrupts the technical discussion and consumes time that could have supported additional testing.
- The conclusion that modern storage costs and limited compression gains generally make CompactOS unnecessary is plausible but lacks direct experimental support.
Linus Tech Tips turns an ill-advised storage shortcut into an enjoyable explanation of how compression evolved and why its usefulness has changed. The historical perspective, understandable technical explanations, and identification of CompactOS make the presentation worthwhile, even for viewers who have no intention of modifying their Windows installation. Although the absence of practical benchmarks and the lengthy promotional interruptions prevent it from becoming a definitive guide, it succeeds as an entertaining and informative exploration of a surprisingly enduring computing problem.
