Purpose of the Game
You want to build a powerful ship with lots of turrets so you can destroy other ships for Loot. You could also play peaceful but at the moment there are only a few game elements. Killing other ships is basically the only thing you can do in late game. Killing other ships will give you a lot of good stuff and the dropped loot will increase your ranking on the leaderboard.
Turrets
When you first create a ship, 2 RC Turrets (Starter) will be present on the walls on your ship. These turrets cannot be looted or dropped through a Cargo Ejector but they can be moved with a wrench to concentrate firepower on one side. More RC Turrets can be obtained via Mining or Trading, more on those later. Another type of turret is simply called "Turret" and must be controlled manually. These are not very useful unless you have a large crew, because it can't be controlled by the helm. Burst turrets and Auto Turrets can also be obtained via Mining or Trading, however, these also can not be controlled by the helm, but are more powerful than a RC Turret or Turret when manned and can be used as a secondary armament.
When building a warship, you should use RCs as your main armament as you can control them as a helmsman (who should be a captain or someone you trust). Secondary armaments are usually a single Burst or Auto, you should sparingly put them on your ship for mining, aiming for specific loot on critical ships and yanking loots.
With the advent of automatic loading systems and thrusters, secondary armaments are often discarded for simpler conveyor designs and faster speed.
Ship Size and Thrusters
Ship sizes in drednot.io are expressed in either the block tiles(how many blocks can be placed on one side), RC count(how many RCs can you put on one side), and world tiles(approximate size to world tiles). For example, a small farming ship with just enough space for 2 RCs on each sides can snugly fit into a 1x1 world tile(and that is what it was designated to do) is called a 1x1 world tile(most common, often only 1x1), 2x2 RCs or 6x6 block tiles. The biggest ship you can expand to is 78x78 block tiles.
It is tempting for beginners to build bigger ships as you can have more health and mount points for turrets. It is often however more beneficial to have smaller ships are they are easier to maneuver and control solo. Beginners should not over-expand their ships(you only need to do it once or twice) and change to a 1x1 when you have a storage ship to store your hard-earned items.
Thrusters are not needed for small ships, but when you build mid-size ships the speed penalty will be significant. They provide a significant thrust toward the opposite side they are mounted to and they automatically rotate to provide sideward thrust. You should observe other players and try their layout when you can build one.
See the ship design guide for more details.
Mining
Valuable materials in this game can be obtained by Mining Diamond Tiles (officially called Treasure tiles) and Flux Tiles, they are denoted by the white diagonally placed square in the middle of the tiles for diamond and green hexagons for flux tiles. You can obtain 1 of the 3 types of "rare" turrets (Auto, Burst, RCs) when the diamond is broken or 1 stack of flux if the green hexagons are completely removed. Those tiles are harder break and you should use slug ammo for maximum gain and high efficiency.
Diamond tiles can be found more commonly in the Sparrows and also in the Finches, but at 1/3rd the rate. Canary and the Pits does not regen tiles but they are created with an abundance of them, also they usually have flux tiles in which clans often race for. However since Canary has a great competition (for its easily accessible flux) it might be better to avoid it until you have people on your side.
Most people use small 2x2 ships for mining and thus they are sometimes called "miner" ships, they can traverse the mine sites efficiently and they can flee easily in the hands of good helmsmen. You can break a block next to you (if you are right next to the block) to make use of 2-3 sides of RCs by sliding to alternate the sides or firing a full corner side (which is your broadside).
Fighting & Ammo Usage
Slug ammo now replaced Breaker ammo but still retained a relatively high efficiency in both speed and resources. That is why you should save the Explosives at the beginning to produce Slug ammo. You can get Explosives by killing Red Bots. Trash ammo is the type of ammo you will most likely use at the beginning of the game, simply because it is free. However, because of update N23, trash ammo slowly decays over time if it is on the floor of your ship or in Expando Boxes.
To conserve your scarce explosive storage when you start off, only use Slug, Sniper, and/or Trash(not recommended for its low damage). Slug ammo has a high mining efficiency second only to standard ammo, Sniper ammo has high damage and high projectile speed perfect for killing bots even for end-game players. Red bots can give you a lot of metal and explosives and are preferred for farming at any stage of the game. DO NOT tackle ships with thrusters and RCs filled on the walls as they are most likely experienced players, it is also not recommended to PVP at the stage as it is not ammo efficient and is detrimental to both sides.
There is a low chance that players will go for any loot you have but if that happens race to the nearest freeport and make Punch ammo to avoid them getting close.
Homeport
By the time you have a few RCs to fill the starter ship's walls, you are already a good target for any pirate to hunt for, to prevent any loss from further mining you should build a homeport at a Freeport. More commonly referred to as Storage ships they are designed to be moored at the Freeport it is built -n and houses facilities for storage, scrapping, trading, manufacturing, and commune. You can convert your current ship or build a new one, the easiest type you can make is by expanding your ship as much as you can(horizontal first) and wrenching out the interiors only leaving a hatch at the highest spot of the ship, more sophisticated ships use expando boxes to store items more efficiently.
It is important to know the trading activities on servers to decide which freeport you want to moor to. Freeports also have clans that might prove troublesome if you are going to moor to the same freeport as your enemy.
Trading & Communication
Trading has been an important aspect to Dredark ever since the introduction of item ejectors and comm stations. You establish an agreement with another player to exchange goods either to trade or barter. You can visit trader ships while parking your ships at freeports, they often list their prices on MOTD and you can ask them to trade in the ship's chat, they are nor obligated to trade with you and can decline your offer when sold out or overstocked so you may need to try a few.
The most common currency in Dredark are Metal, RC's and Flux.
Inter-ship communication in drednot.io is done by either sign posts or comm stations, comm stations are only used for announcements now as they occupy ship space and your chat is broadcasted to the entire server. Ship to ship communication is done by placing sig posts with your ship parked near them. You can also use the Dredark discord server to chat with other players and share information.
Team Management & Griefers (Trolls)
It is recommended to set your ship to Private at first because then no Trolls or Griefers can join your ship. Once you have built a guest spawn point and limited the amount guests can walk, you can set your ship to public. Only promote guests to the crew rank once you have accessed their attentiveness, such as making them read the Motto and trustworthiness. If a promoted Guest turns out to be a troll, ban them fast before they ruin your ship. Keep guests and untrustworthy crew off of your ship when you leave the game. You will find in the ship menu a "Save Ship" button to kick all people on your ship. However, you need to be in a safe zone (Freeport I, Freeport II, Freeport III) to save. If you do not save they can rejoin and control your ship. That is a death sentence for your ship in most cases. To avoid this, you can set your ship to "Invites-Only", like that, only captains and invited-members can enter your ship. Only promote those that you're sure you can trust to be captain, because they can reload your ship even after you have saved it.