These crawls are part of an effort to archive pages as they are created and archive the pages that they refer to. That way, as the pages that are referenced are changed or taken from the web, a link to the version that was live when the page was written will be preserved.
Then the Internet Archive hopes that references to these archived pages will be put in place of a link that would be otherwise be broken, or a companion link to allow people to see what was originally intended by a page's authors.
This is a collection of web page captures from links added to, or changed on, Wikipedia pages. The idea is to bring a reliability to Wikipedia outlinks so that if the pages referenced by Wikipedia articles are changed, or go away, a reader can permanently find what was originally referred to.
In computing, SISD (single instruction, single data) is a term referring to a computer architecture in which a single processor, a uniprocessor, executes a single instruction stream, to operate on data stored in a single memory. This corresponds to the von Neumann architecture.
SISD is one of the four main classifications as defined in Flynn's taxonomy. In this system classifications are based upon the number of concurrent instructions and data streams present in the computer architecture. According to Michael J. Flynn, SISD can have concurrent processing characteristics. Instruction fetching and pipelined execution of instructions are common examples found in most modern SISD computers.[1][2]
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