Smalltalk adds to game lore and it is a means to acquire unique thingsrewards:
Please follow the above links for
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details but in short:
- Trade Agents provide up-to-date information on trades at stations.
- Smalltalk discounts are different to other discounts so they are a stackable, additional option.
- You can ask for info on the better-skilled NPCs in the area.
- Virtual Seminars allow you to train one of your NPC's skills (addition of a star).
Note: While setting up your trade agent network it will be useful to at least scan the Administration dock of every station. This will enable you to target a dock with a guaranteed Engineer if you need one for emergency Skunk repairs in the future!
While <player> is docked on stations, NPCs will occasionally start talking, and when they do a speech bubble appears over their head to help identify them in a crowd.
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** A score of 4+ for all 3 minigames.
Trade Agents
These will only be offered by a subset of NPCs.
NPCs that can offer Trade Updates:
Inventory item traders (eg Food Merchant, Arms Dealer, Recruitment Officer or Black Marketeer).
License broker
Mechanic
Police Chief
Ship Dealer (unconfirmed)
Specialist
Non-hirable station crew (they are working on the station) - typically found on Administration platforms (ie Defense Officer, Engineer, Manager).
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Discounts for stations or traders
A smalltalking NPC can offer a discount at their station, which offers higher profit margins if taken advantage of.
After successfully smalltalking an NPC Trader (e.g. Black Marketeer, Arms Dealer or Mechanic; Recruitment Officers too), they may offer a choice of station or personal discounts. Station discounts from smalltalk apply on top of any other discounts, such as via Standings (Reputation) or those found outside stations whilst investigating station i-points or other areas. Therefore they can all be stacked up to gain a higher profit margin than would otherwise be available.
Station discounts do not apply to shipyards as they don't produce anything other than ships. However they do apply to any other station's products. Shipyards will only usefully provide comissions (ie 'sell us that <ware>' at a bonus rate, rather than 'buy this <ware> from me' at a discount)
(This may need to be investigated: does a ship dealer apply a discount to components or drones ordered with a ship? - Snafu)
Solomon Short wrote:
"The Station discounts/commissions apply to all relevant trades with that station for duration.
You can also keep wandering around (&/or visit other docks on the station) to find more opportunities to unlock them, stacking them up.
So if you pick which stations you seek them on (I believe they're usually for station the NPC you game with is on) you can hope to apply them to expensive wares (which can be handy when you've got discounts on station building supplies)."
Location and skill visibility for hirable, well-skilled NPCs
These options only point to NPCs with unknown skills, so there could be other NPCs available to hire within range that won't be highlighted if their skills are already known. It makes sense to use these options where there are a lot of NPCs of the type you are interested in (e.g. see sidebar for zone-wide, or station dock menu to check platforms or station population).
More expensive hires are usually better skilled, but be aware that their cost is based upon their /total/ skill list, not simply the primary skills for their job.. so you could end up with a Captain who is rotten in Navigation and Leadership but excellent in Science & Management.. 
A useful point WRT hiring: find a station & target a dock. Then open the (I)nfo bar; you will now see all NPCs at all docks on the station. Find a suitable dock with <many> of the NPC type you wish to hire & dock there, using mission guidance if necessary. You can then smalltalk (to lvl1) any appropriate NPCs for free to discover the skills of the desired NPC; after that's done hire as necessary once their skills are known
NPCs randomly disappear from stations (but not docks if you're landed) to simulate personnel 'churn'. If you dock at one point & find a good NPC, don't expect them to remain there once you've docked at another point; leaving the zone will almost guarantee the NPC changearound*
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Collecting Virtual Seminars
Successful completion of the third smalltalk allows 'Virtual Seminars', which are easiest to come by via Smalltalk (they're now (v4) occasionally available via mission rewards or 'yellow ping' lockboxes too).
They are available for various potentially important skills, such as Engineering, Leadership and Morale: a Seminar can be used to add one star to the related skill of any one of your hired NPC's primary, bold-highlighted skills (eg only Engineering for Engineers, but Leadership or Navigation for a Captain), to a maximum of 5 stars. Exactly which Seminar you may be offered relates to the primary skills or the type of the NPC in question so it is somewhat random, in the sense that it is random as to which NPC may begin a smalltalk. Boarding experience for Marine Officers can only be gained through.. heh.. experience, and it's slow (around +(2d6+2)% at L4 per successful boarding), so be warned!
Seminars are only available through smalltalk after the Give (craftable) Gift option if the first smalltalk was completed with a score of 8+ points in 2 minigames and if the second minigame session was completed with a score of 4+ points in all 3 minigames. A higher (maximum?) score in the second minigame stage can increase the range (number) of seminars offered, depending upon the smalltalked NPC's class. <Player> can only pick 1 seminar as the prize, no matter how good the score.