For general connectors:
Description 1:
2 X 12 WAY HEADER ST M
|   |      |      |  |
|   |      |      |  GENDER
|   |      |      ORIENTATION (ST or RA)
|   |      TYPE
|   Number of rows
Number of columns
|   |
For some connectors it is simply x WAY

For RF connectors:
A B C D
| | | |
| | | GENDER (P or J)
| | ORIENTATION (ST or RA)
| IMPEDANCE (50R or 75R generally)
TYPE (SMA, SMB, MCX, MMCX, SMP, BNC etc)

If unsure, for other types of connectors see library "components" spreadsheet.

Description 2:
A B
| |
| Manufacturer's part number 
Manufacturer (NOT USED FOR SAMTEC)