The terms are used together, you can line or sleeve, its the same process. There are differences though in the design of them. Some are joined as sets (wet liners often are but not always)There are top hat types, often used in diesel systems (used to be preferred as the top hat was supposed to stop movement - didn't always work, they would crack the hats off).

Nicasil is a brand coating, has to be used with specific piston rings to allow seal, very similar to 2 stroke bore coating.
Ductile is a process not a brand, the process is how the liner/sleeve is made. The iron content is spun to remove impurities within the casting therefore making them stronger and less likely to fail.
If you want to talk sleeves/liners ring Westwood engineering. They make 99% of the liners out there these days.

They are not as expensive as people think, fitting them correctly on the other hand makes the success.