The file
Pastel ponies with brushable manes and a symbol on the flank, sold six at a time. The original line, now called G1, ran the whole decade and came with a stable, a castle and a Dream Beauty parlor.
It was the girls'-aisle equivalent of He-Man: collect them all, watch the cartoon, beg for the playset. The '80s ponies are the ones collectors want, especially with the original combs.
Sources: Wikipedia — My Little Pony