Noob Question.

This has to do with the ship currently selected in the shipyard if you select user these are one you created and will appear on the tech same with core ships except they are predesigned..

and if you select all you probably see all of the ships on the tech tree..

not all shure myself...

When a tech advocates the coming of new ships, it only does so when all other tech requirements are met as well. See it as being "needed" components, rather than "sufficient" ones. This is confusing the first times you play the game, but you get used to it.

So if, for instance, your previous Skeeter design was something in the lines of:

• Tiny Hull
• 2 x Laser II
• Titanium Armor III

...then the Skeeter design will pop up in the tech displays of Laser II and Titanium III (since you start with Tiny hulls, you have no need to research them anymore). However, you can't build it until you have all the required components. So if you researched Laser II, it would say you'd gain the Skeeter design, but you'd actually still need Titanium III.

Hope that answers your question,
Tarbo

there is a comment about the number of tech needed with the ship?

Every ship can have some techs needed for being available, this can be the weapon, the defense, the drive, the miniaturisation ect...
For example, you want to build ships with missiles as weapon and armor against mass driver, you search a new missile that open access to a new ship, but among the techs needed there is a tech against missile as protection and not armor. Then if you don't search missile protection until the tech needed you will not get this ship.