With any scale you learn, it is important to know how each note of the scale relates to the root note or key note. Any note can be given a scale degree which shows its relation to the major scale of the same key, even if that note is not contained in the major scale itself. It is worth comparing the notes of the minor pentatonic scale with those of the major scale. Shown below are the note names and the scale degrees of both scales in the key of C.
Notice that the minor pentatonic scale does not contain the degrees 2 or 6, and that the 3rd and 7th degrees are flattened. Play through the C minor pentatonic scale several times, naming the scale degrees as you play each one. When you can do this from memory, transpose it to other keys by moving it up or down the fretboard and notice that the scale degrees remain the same regardless of what key you are playing in.