Star Trek

The Measure of a Man--good on so many levels. Humans, in general, tend to regard sentience as belonging solely to them.

Clues has always been my favorite Data-related episode. Such great scenes, especially between Picard and Data.

I agree with randy kerr.  The episode where Data plays Sherlock Holmes was my favorite.  Title??

Are you thinking of the episode "Elementary, My Dear Data"?

The Offspring

either Measure of a Man or In Theory Love Love Love Data. 

thats a hard one, I like Descent parts 1 and 2 and brothers was good too

My favorite Data episode would more than likely be "Clues". I LOVE that one! And I always love when Data "initiates emergency procedures". =D

Data's Lady Fans have been strangely quiescent, as of late ...
and they are certainly a very vocal group ... I can vouch for that!

Any TNG episode where Data had a chance to stand out is a great one! I love "Measure of a Man" (to this day Maddox makes my blood boil!), "Brothers" (Brent Spiner's talent to play all 3 characters is unbelievable), “The Outrageous Okona” (loved Data’s understanding humor storyline with Joe Piscopo), “The Schizoid Man” (love watching the heart-wrenching drama of Data's split personalities) and "Deja Q" (the best part of that episode is Q's gift of laughter to Data at the end after Data helped Q adjust to being human).  But of course I'm biased because Data's near & dear to my heart (I turn Nemesis off after he leaves Geordi & jumps to Shinzon's ship)

Julia

I can't single out a single, BEST episode for Mr. Data,
but the colourful metaphor he used in GENERATIONS
was priceless! Who'd have ever expected it? Not I ...

The Offspring is undoubtedly my favorite Data episode to date. It just stands out as the best episode that focuses on Data and his character development, in my opinion.

Ooh, so many to choose from.  Data was definitely the Spock of TNG, constantly stealing the show, even one-upping the resident alien, Worf, on a regular basis.  However, in an attempt to answer the question, the episodes which I feel are my favorite and/or best representations of Data as a character include:

"The Offspring" (the one with Lal)

"Elementary, Dear Data" (the first Sherlock Holmes episode)

"The Measure of a Man" (his freedom/sentience is on trial--my personal favorite)

"Redemption II" (Data is CO of the Sutherland during Klingon civil war/Romulan blockade--IMO, the best executed of the Data-centric episodes)

"A Fistful of Datas" (Alexander takes Worf to the Ancient West with disaterous results--not my favorite and far from the best, but so goddamned funny)

"Data's Day" (A letter written to Cmdr. Maddox explaining his day-to-day interactions--again, not my favorite, but GREAT insight to Data as a developed character)

"The Ensigns of Command" (Data has to convince colonists to move before they're eradicated by teh Sheliak, destroys the colony's watyer system to prove a point--this is the first look we REALLY get that shows what Data can really do on his own, he's not just a computer following orders, but an individual capable of making decisions.)

However, my favorite Data episode isn't even Data-centric... "The Naked Now"... because data is fully functional, programmed in multiple techniques... and Denise Crosby was SLAMMIN!

I did not like the Lore stories... I don't know why, he just rubbed me the wrong way. The storylines felt contrived to me.