The services window provides you with an interface to all the services available in the system (if any at all). At the top of the window you will see the amount of credits you have available and also the amount of hold space for your current ship.
When buying or selling, generally you will be using your credits as payment. Additionally, some purchases (like for ships) also have a skill and crew requirement.
In most cases, services can be filtered and sorted to find what you are looking for quickly. Sorting is achieved by using the columns headers of tables and filter boxes can be found in table footers.
Below shows a list of services that can be potentially be available in a system, depending on the structures that have been built.
You can purchase a book once with each book providing you with an increase in a specific skill, as noted in the books' description.
Food and drink can give you a temporary buff or debuff to one or more of your characters EIDOS statistics, for a certain amount of time when consumed. You can only consume one food or drink item at a time and cannot consume another until the effects have worn off.
Medical services are for healing your character, replenishing their health. There are various options available each with a different cost.
If you are an android then you will rely on illegal amenity services for food, drinks and medical triage. Food and drink works the same as for other races when you are an android, but the choices will be widely different. Medical triage also operates in the same manner but again, the choices will be different.
Casino games can be played when within a 10 light year range of a system that provides this service. Currently, the only casino game available is slots, which allow you to gamble credits with low, medium and high-stakes.
Crew members can be hired for different costs depending on their level and role. A certain number of crew are required to operate some ships, but crew also provide other benefits. Some crew have the ability to improve your EIDOS statistics, while others can help fly your fleet of ships or improve your mining yields.
If your faction has built a treasury in the system, you will be able to deposit credits into the treasury. You cannot take credits back out from the treasury but credits fund research of equipment, ships and weapon lines for the faction. Some rival players may also attempt to steal from the treasury via hacking skills.
Meditation is available for humans and clones and can be used to slowly adjust your factors in any direction. Different factors levels and skill point combinations reveal new skills to realise. Androids cannot mediate but have instead the ability to use software patches.
When travelling at FTL speeds your ship consumes fuel to replenish charge. The ship refuel service provides a mechanism to instantly refuel your ship for a low cost.
If your ship is damaged in combat you can repair it for a flat cost, back to full strength (note a ships shields recharge over time and cannot be repaired). Additionally, with this service available you can also repair damaged ports from the tactical window. Only ports above 50% fatigue can be repaired and they can only be repaired back to 50% fatigue (used condition).
Rooms provide access to skill training for both yourself and crew members aboard. If available and you have enough space, you can purchase and fit rooms from a large selection of options.
If you are looking to expand your fleet or just a new ride, you can purchase new ships from any system that has the ship trading service. To purchase a ship not only will you need enough credits, but also enough crew to help you operate the vessel and meet any skill requirements. Clicking into the details of any ship will state all the criteria you must meet and whether you meet them.
Once you purchase a ship it will be parked at the system location. If you want to use the ship you can do this from the command window, by finding the new ship within parked ships. Different factions offer different ships including some player factions, which may have researched and built their own.
If you are unsure on which ship to buy, in the computer window there is a section that shows all ships you can command at your skill level with various other filters for helping with purchase decisions.
Buying and selling commodities is one of the fundamental trading mechanics within the universe. You can buy commodities that are available at this system as long as it is not provided by your own faction (in which case you can just transfer the commodities for free). Some systems also provide the service to trade illegal commodities.
Consumables are items that are generally consumed or traded and come in many different types. Consumables are often needed to complete missions or for crafting and there are some consumables that are meant for just humans, clones or androids.
Parts are used for crafting or construction and can either be equipment parts, ship parts, weapon parts of structure components.
Ports refer to equipment and weapons you can fit to your ship - if you have available power to do so (you can check in the tactical window). If you do not have enough power to fit a port, you can also choose to store the port during the purchase flow - in which case the port is stored in your ships hold.
Equipment tend to be items like afterburners that can increase your speed or mining beams to improve your mining yield. Weapons are for spatial combat and come in many types and damage profiles. Ports do fatigue through use but can be repaired in any system with the ship repair service.
You can pay for skill training for your character to increase their level in a chosen skill. Achieved through Substitute Reality (SR), each skill has a different price depending on the skill itself and its level. The improvements occur over time with a small boost when you start the course.
SR Training is a dangerous endeavour and can sometimes cause massive deductions instead of improvements if it goes wrong.
Although not a service available from the services window, if there is a stable wormhole in the system, then a wormhole travel service will be noted. You will find the endpoint of the wormhole as a remote system listed in the helm window, engaging to this remote system via FTL will take you to the endpoint. By using a wormhole you can shortcut journeys across the universe, but often this convenience comes at a toll cost.