This will be a series of notes I make on my observations of the changes in character and technology over the episodes. I have watched the Original Series once and recently so some things strike me as notable.
In the first Episode called “Man Trap”, Dr McCoy is a lot more serious. Spock shows some emotion (even smiles a little in the end!!). The two aren’t at eachother’s throats with sarcasm yet. Uhura almost flirts with Spock. Sulu is found in the Botany department special food served by Janson and takes his place on the bridge at navigation only at the very end! No sign of Scotty or Chekov. Phasers and effects are low-tech. Stun is a red beam which pops and leads the target unable to think or move- unlike later episodes, it is not green and doesn’t make them unconscious. Slow pace.