////could you please define "parallel" and "paralleling"? I do not know what the term means,////

There are various ways of paralleling. Guitarists tend to play a series of chords that have the same hand shape and fingering up and down the neck. It usually betrays an inability to find a more musical solution. Like anything else in music, paralleling has its uses but has become a bad habit in modern guitar-playing.

Folk bass that uses root-fifth is paralleling. Why? Because it's root-fith, root-fifth, root-fifth. You can move up and down the fingerboard but if all you're playing over and over again is root-fifth, that's paralleling. It's not wrong to do unless you're doing it all the time. It became problematic a tetrachord 7th such as an Eb minor 7th. You can't play Eb on the open E-string obviously since that it is lowest note on the bass (we're not counting 5-stringers or neck extensions). So you have to play Eb on the D-string but your 7th ends up at Db on the G-string. That's ok to play on occasion but certainly not every time you play it. So you invert the Eb minor 7th chord by playing the Eb on the D-string but then playing the Gb on the E-string, the Bb on the A string and then the Db on the A-string. That sounds much better if you're coupling it with, say, an Ab major 7th. If you play it parallel with the way the Ab major 7th is played, you're going to climb the neck everytime you play the Eb minor 7th. Inverting it is non-parallel and far more musically aesthetic.