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+# 100 predictions
+
+Para la versión en español, ve a [aquí](nunosempere.github.io/rat/100-predicciones)
+
+## Day 1
+{SHA is an acronym for "Secure Hashing Algorithm"; a hash algorithm recieves a string, or more generally a document, an returns a number.
+Thus, a hash can identify a document, such that the hash can be revealed without revealing the document. 
+If the document is published afterwards, people know it hasn't been changed (because the hash would also change)
+
+In 2017, a project by CWI Amsterdam and Google produced 2 different legible pdfs which had the same SHA1 hash.
+This makes SHA1 insecure; it is no longer enough to uniquely identify a document.
+
+The hash family continued with SHA2, and then SHA3. The most secure version of SHA3 is SHA-512.
+
+Questions
+- What probability, per year, do you assign to SHA-512 being successfully attacked?  
+By successfully attacked, we understand that someone finds x, x' such that SHA3-512(x) = SHA3-512(x'), or that given a
+y = SHA3-512(z) someone finds a z' =/= z such that SHA3-512(z')=y.
+- WHat probability, per year, do you assign to SHA3-512 being replaced as a standard?}
+
+Recommended time: 15 mins.
+
+## Hashes
+Everything between {} is hashed through SHA3-512 (https://www.browserling.com/tools/sha3-hash), and published on Twitter (@NunoSempere)
+
+### Day 1
+0addb6466a2fb3a537fa276e39306f2b57f8d31e66b826f57b62d141ff3de821fca5b9e35de06092c3847bc018b1531ecc3123e09b0f137700c2433b58f8781f