1: What is the item database? Why should I use it?
Well, it's a list of the items and ships in Pirates of the Burning Sea, along with their stats, recipes and stuff. It's so you can easily find information and it's presented in an easier to use format than the ingame help.

2: How do I navigate through the Item Database?
From the start screen, simply click a category on the left to start browsing through the items. On the right you'll see options to switch the view - Recipe View shows the recipes for that item (or for all items in that category); click Item View to switch back. When viewing a category, click Show Full to display the full data for each item - this might take up quite a bit of space though. You can tick two items and hit submit to view them side by side. Finally, when you're viewing an item you can click Show Full Production Line to show the item's recipe expanded fully - for example, Oak Blocks are made in the recipe 'Manufacture Blocks' , which uses Oak Logs, which are harvested using 'Oak Harvest'. Rather than having to click on Oak Logs in the recipe, the full production line view shows you the whole thing from top to bottom.

3: Your values are different to those in the spreadsheet...
That's not a question.

3a: Why are your values different to those in the spreadsheet?
Better. There's a couple of reasons for that. Firstly, the spreadsheet rounds up a bit more often than I do. Secondly, the spreadsheet has been set to give distorted values to items produced from some recipes that have more than one output. For my calculations the output value is set to (total value) / (number of items output). Smelt Silver for example produces 2 lead and 2 silver - in my calculations it's considered that because you get the same amount of each they each cost the same to produce. Same with Molasses and Refined Sugar, the values of which are doubled in the spreadsheet.

4: Why do Hulks have a value of 1? / Why are (Captured) deed values so low?
As an item of loot, a Hulk has no inherant value so one cannot be calculated.

5: How come a Mark of Victory costs 2534db? / Where did you pluck the Refit costs from?
The cheapest way of getting a Mark is through pvp victory, but as that amounts to an inherant value of 0, I instead used the cheapest bundle handin as the basis of Mark of Victory cost.

6: What's this stuff in Special Ship Outfitting?
No idea. It was in the game docs under the grouping "Ship Outfitting" during beta.

7: What is this Coldfront Ship Rating?
Because ships in PotBS have so many stats it can be hard to see which is the best choice. The Coldfront Ship Rating is an easy way to compare the value of ships which weighs up the speed, maneuverability, size, armor values, damage resistance, crew size, cargo hold and damage per second at both 200yards and 400yards. How all those values affect the rating is rather obvious, apart from perhaps ships size rating (ie, small, medium, large, huge, colossal). For this I would give a smaller ship a better rating than an otherwise identical ship of a larger class, because outfitting gets less effective as the ships go up in size (eg, Small Accuracy Gun Rig 6 gives +8 accuracy, but the best Colossal Accuracy Gun Rig only grants a +3).

8: Your maths is wrong! / The info is wrong!
Quite possibly as I am only human.. send a mail to xaphod at coldfront dot net with full information and I'll fix it.

9: How did you get the ship stats? How did you get the names from the hash values?
I didn't do anything nearly as complicated as that, I just inputted all the data manually.. see my answer to number 8..