Parallel Connection of Bulbs:
When bulbs are connected in parallel, each bulb is connected directly across the supply voltage. This means that the voltage across each bulb is the same. In a parallel circuit, the total current is divided among the bulbs, and each bulb receives the same voltage.

Advantages of parallel connection:
1. Each bulb operates independently: If one bulb fails or is removed, the other bulbs will continue to operate.
2. Bulbs can have different wattages: Since each bulb receives the same voltage, bulbs with different wattages can be connected in parallel without affecting each other.
3. Brightness is not affected by adding or removing bulbs: The brightness of each bulb remains constant regardless of the number of bulbs connected in parallel.

Series Connection of Bulbs:
When bulbs are connected in series, the current flows through each bulb in succession. In a series circuit, the voltage is divided among the bulbs, and the total resistance is equal to the sum of the resistances of the bulbs.

Disadvantages of series connection:
1. If one bulb fails or is removed, all bulbs in the series circuit will turn off: This is because the current is interrupted in a series circuit if one component fails.
2. Bulbs must have the same wattage: Since the current is the same in a series circuit, all bulbs must have the same wattage to ensure they receive the appropriate voltage and do not burn out.
3. Adding or removing bulbs affects brightness: The brightness of each bulb decreases as more bulbs are added in series, and it increases if bulbs are removed from the series circuit.

Comparison:
Based on the advantages and disadvantages mentioned above, it is preferable to connect bulbs in parallel rather than in series. Connecting bulbs in parallel allows for independent operation, the use of bulbs with different wattages, and consistent brightness regardless of the number of bulbs. On the other hand, series connection limits the options for different wattages, causes all bulbs to turn off if one fails, and affects brightness when adding or removing bulbs. Therefore, parallel connection is the preferred choice for connecting bulbs.