These are points needed to buy certain guild-related items. After reaching Novice rank (attainable with skill level 28) in a Guild, and signing up with a Guildworker's Union Representative for that guild, you can trade requested items of that craft to the Guild Representative for Guild Points. The amount of points you can earn each day varies from day to day.
The FFXIAH Guild Pattern has been out of date for several years now, not reflecting the 3x multiplier applied to all daily maximums or several guild point item changes away from items that required NM drops or required excessive numbers of turn-ins for their associated crafting rank. Always double-check linkbacks to other wikis to ensure you don't get the wrong item or wrong amount of items to cap points on any given day. Double-checking with the Guild Representative first before pursuing the item is also recommended (and easy to do), and the info will never be wrong.