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  "body": "\n## Summary\n\nA subshift of finite type is a [[shift space|A1XE59ZHNM]] described by a finite list of forbidden words.\nAfter a recoding of the symbols, every subshift of finite type becomes the set of bi-infinite walks on a finite [[directed graph|0KFYGSHHF5]].\nThese spaces are the basic models of [[symbolic dynamics|EWFWTSVY0B]].\nThrough [[Markov partitions|4VNHVDHTNN]] they also code hyperbolic smooth systems, so questions about such systems become questions about matrices.\n\n## Explanations\n\n### L1 human\n\nThink of an infinite sequence of symbols, written in both directions.\nA subshift of finite type allows every such sequence except those that contain some word from a fixed finite blacklist.\nFor example, take the symbols $0$ and $1$ and forbid the word $11$.\nThen the allowed sequences are those in which two $1$s never stand next to each other.\nWhether a sequence is allowed can always be checked by looking through a window of fixed width.\nSee the [[definition|M7RPDE39FM]].\n",
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