Video slots are essentially of three kinds, and so are the reel options. The free reel online slots have 3, 5 and 7 reel formats. The 3 reel free slots are the simplest, while the others fall under the complex category. The reels of the free slot machines online are arranged in vertical spaces and with the hit of the spin button, they start rotating. The numbers are chosen by their luck potent by numerology.