Round 2: Bits and data

(A hexadecimal bit map that indicates the primes in the first 2048 odd integers.)
Learning objectives
In this round you will learn …
… that data is a sequence of bits consisting of one or more fixed-length words
… that the bits acquire meaning only through an agreed format for the data
… that numerical data is formatted according to the binary number system
… that textual data is formatted as a sequence of binary character codes (*)
… to read and write bits using hexadecimal (=a shorthand for binary)
… to operate on the bits of a word with word operations
(Material that is marked with one or more asterisks (*) is good-to-know, but not critical to solving the exercises or passing the course.)