private static String toHtml() {
        DocumentedType[] types = {
            BOOLEAN, INT8, INT16, INT32, INT64,
            UNSIGNED_INT32, VARINT, VARLONG, UUID, FLOAT64,
            STRING, COMPACT_STRING, NULLABLE_STRING, COMPACT_NULLABLE_STRING,
            BYTES, COMPACT_BYTES, NULLABLE_BYTES, COMPACT_NULLABLE_BYTES,
            RECORDS, new ArrayOf(STRING), new CompactArrayOf(COMPACT_STRING)};
        final StringBuilder b = new StringBuilder();
        b.append("<table class=\"data-table\"><tbody>\n");
        b.append("<tr>");
        b.append("<th>Type</th>\n");
        b.append("<th>Description</th>\n");
        b.append("</tr>\n");
        for (DocumentedType type : types) {
            b.append("<tr>");
            b.append("<td>");
            b.append(type.typeName());
            b.append("</td>");
            b.append("<td>");
            b.append(type.documentation());
            b.append("</td>");
            b.append("</tr>\n");
        }
        b.append("</tbody></table>\n");
        return b.toString();
    }
The Boolean type represents a boolean value in a byte by using
the value of 0 to represent false, and 1 to represent true.

If for some reason a value that is not 0 or 1 is read,
then any non-zero value will return true.
clients/src/main/java/org/apache/kafka/common/protocol/types/Type.java