OCR H446 · Component 01

1.3.1 Compression, encryption and hashing

Lossy and lossless compression, run-length encoding, dictionary coding, encryption, symmetric and asymmetric keys, hashing, collisions, rainbow tables, salts, and checksums.

Topic overview

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Encode AAAACCCBB using (count,character) run-length pairs. If each count and character occupies one byte, compare sizes.Apply
What is compression?Compression
Why do we compress files?Compression
What is lossy compression?Compression
What is lossless compression?Compression
How does run-length encoding work?Compression

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