Ensign Daniels was an operations division Starfleet transporter chief assigned to the USS Enterprise-D under Captain Jean-Luc Picard during the late 2360s.
Daniels was addicted to the Ktarian game and was sitting in Ten Forward ecstatically playing the game. (TNG: "The Game")
She was working on an aft station of the bridge when the ship went into the FGC 47 nebula and made contact with a new lifeform (TNG: "Imaginary Friend") and when the Borg Hugh was beamed aboard the ship. (TNG: "I Borg")
In late 2368 she was treated in sickbay by Diana Giddings and Martinez while the Enterprise-D assisted a damaged Romulan science vessel. (TNG: "The Next Phase")
She operated the transporter and beamed the away team back from Devidia II including Samuel Clemens. Riker then ordered her to call security for the guest from 1893. (TNG: "Time's Arrow, Part II")
In 2369, Ensign Daniels was assigned to the transporter room where she beamed Ambassador Ves Alkar and his "mother" Sev Maylor aboard from the transport vessel Dorian. Daniels was later responsible for beaming Alkar, Jarth, and Liva down to Rekag-Seronia when Deanna Troi entered the transporter room with a knife and lunged towards Alkar. When Captain Picard tried to intervene, Troi knocked him down and Daniels ran over from the transporter console, where she was able to restrain Troi and pull her off of Picard. (TNG: "Man of the People")
Daniels was played by recurring background actress Dru Wagner who received no credit for her appearances.
She was identified by name in the script of the episode "Man of the People". Her name is only mentioned in the cast list, while the rest of the script only calls her Transporter Chief. 
Her lines "Aye, sir." and "
Yes, captain." in "Man of the People" were voiced by an unknown actress.