====== Chess - Programming - Polyglot Book Format - File Format ======

Polyglot files are usually named with a **.bin** extension.

The files contain one or more entries with each entry having the following information:

<code cpp>
struct entry_t {
   uint64_t key;
   uint16_t move;
   uint16_t weight;
   uint32_t learn;
};
</code>

<WRAP info>
**NOTE:**   All integers are stored highest byte first (regardless of size).

  * The entries are ordered according to key; Lowest key first. 


Sometimes the file format is shown as:

<code cpp>
struct entry_t {
   uint64_t key;
   uint16_t move;
   uint16_t count;
   uint16_t n;
   uint16_t sum;
};
</code>

  * This still represents the same data.

</WRAP>