Lighting is the most important factor in indoor gardening, and often the biggest financial investment. Outdoors, the sun provides more than enough light energy for plants, but growing seasons and conditions vary widely in different parts of the country. Plus, many people simply don't have the space for an outdoor garden. As long as you have adequate light, an indoor garden can provide you with fruits, vegetables and herbs year round, regardless of what is happening outside.
HID lighting is the standard for the industry of indoor gardening. There are 2 types of bulbs Metal Halids & High Pressure Sodium. Metal Halids are great for vegetative growth stage and High pressure sodiums are perfect for the fruiting or flowing stages. These lights are most out put and highest yield but the most costly to run.
CMH (ceramic metal halid) lighting is a variant of HID lighting they come in 315 watt bulbs the cover a 3ft x 3ft area they have a great spectrum and they are more efficient then traditional HID however are more costly up front.
Florescent lights are prefect for clones, seedlings and even during early and mid vegetative stages of growth how ever they don't preform well in flower, because they lack the power to penetrate the canopy.
LED Lighting is typically great for vegetative growth and for mother plants how ever falls short during flower due to the lower power nature of LED lights, generally very cheap to run but tend to be very expensive to purchase.