Jeremiah "Jere" Gettle has always been passionate about saving seeds.   He is the founder of Baker Creek Heirloom Seeds, and speaks to CHOW at  his seed bank in Petaluma, California.
I saved this video before I decided to start a garden, and looking back at it realized it's where I got some of my seeds from:) Great source!
What Are Heirloom Seeds?
 Heirloom seeds, heirloom vegetables and heirloom gardening are  becoming increasingly popular today. Many people are turning or  returning to home gardening for a variety of reasons, and heirloom seeds  figure prominently. Some of these include an interest in fresh, local  and healthy foods; others need to stretch the family food budget; some  need additional exercise, preferably outdoors; and still others are  searching for the lost flavors of the family garden when they were  growing up.
All of this interest has created some confusion as to what an  heirloom seed truly is. Some think that the term “heirloom” is the same  as “organic”. Other folks think that anything that is not organic or  heirloom means that it is GMO. To make matters worse, some larger seed  companies sell both heirloom and hybrid seeds that are certified  organic, further confusing the matter.
Let’s take a look at a few definitions so we can better understand  what an heirloom seed is compared to a hybrid or genetically modified  seed.
An heirloom is anything of value (though not  necessarily economic) to a person, family or group passed down from one  generation to other. Examples are furniture, China, silver or seeds. An  heirloom is generally considered something worth passing down. An heirloom seed,  therefore, is seed from a plant that has been passed from one  generation to another, carefully grown and saved because it is  considered valuable. The value could lie in its flavor, productivity,  hardiness or adaptability. Many heirlooms have been grown, saved and  passed down for more than 100 years. Some have history reaching back 300  years or more. To have been saved and preserved for so long, these seed  varieties have shown their value to many people and families for an  extremely long time.
Most heirlooms have been saved and selected because they have the  best flavor and production in home and small market gardens. We get the  benefit of this long development cycle, as only the best producing, most  flavorful, most memorable and most dependable varieties have made the  selection throughout the years. Delicate, weak or fickle varieties are  no longer with us.
Open-pollinated is another term sometimes used  interchangeably with heirloom. They do not mean the same thing, as an  open pollinated seed is simply a variety where the seed can be harvested  from the plant, saved, replanted, and the same variety will re grow  year after year. This is how we have the heirloom varieties that we have  today is because they are open-pollinated. All heirloom seeds are open  pollinated, but not all open pollinated seeds are heirloom, as there are  new open pollinated varieties being introduced that are obviously not  old enough to be considered heirlooms. An example of this is the Oregon Spring tomato  developed by Dr. Baggett, Oregon State University through traditional  plant breeding for early germination and productivity in the cool Oregon  spring.
Organic certification is the process of certifying a  crop grown to a strict uniform set of standards. The certification  process includes inspections of farm fields and processing facilities,  detailed record keeping and periodic testing of soil and water to ensure  that growers and handlers are meeting the standards which have been  set. The USDA sets the standards, and the criteria for meeting those  standards. The certifying agency such as Oregon Tilth, CCOF, QAI and  OCAI verifies that the grower is meeting the standards set by the USDA.  In short, “organic” means only that a crop was grown to a specific set  of standards.
A hybrid seed is produced by artificially cross  pollinating two genetically different plants of the same species, such  as two different tomatoes or two varieties of corn. The cross  pollination is done by hand, and a seed that is saved will not grow true  to either parent. Thus the farmer or gardener has no choice but to  purchase new seed each year. Hybrids are typically bred for commercial  use and profit to change the characteristic of the resulting plants,  such as higher yield, greater uniformity, more even ripening, improved  color and disease resistance. Flavor has only recently begun to be  addressed when selecting characteristics for new hybrids.
Hybrids originated in the 1920s and 1930s for small local commercial  growers who shipped their produce less than 50 miles to market, and  needed more consistent production for a steady supply of fresh produce  to the markets. Taste and freshness were still important than, as many  people living in the city were recent transplants from the country, and  still remembered what fresh produce tasted like. This is completely  different from the hybrids of today with the selected characteristics  that have resulted in the iconic colorful yet flavorless supermarket  tomato that looks and tastes the same year round.
Genetically Modified Organisms or GMO  seed have been altered using DNA from completely different species and  organisms to give different traits such as resistance to herbicides and  acceptance of chemical fertilizers. Some GMO corn, for instance,  manufactures its own herbicide in its root structure. Some DNA donors  have come from fish, frogs and bacteria. The major crops that are  genetically modified are corn, cotton, soybeans and wheat. Sugar beets  and alfalfa have recently been deregulated, and potatoes are being  studied. Most common garden vegetables are not yet genetically modified  simply because the financial return in the market is not present yet.
Two of the better known benefits of heirloom seed include  adaptability and flavor. Some varieties of heirloom tomato have been  known to adapt to a specific location within as little as 2 to 3 growing  seasons, showing better vigor, better production, better flavor and  increase disease resistance. This is a result of saving the seed and  replanting it year to year. Many people come to heirlooms in search of  flavors that they experienced as a child. One of the leading  characteristics of heirloom varieties is defined by the depth of flavor  that they produce. This single characteristic has been one of the major  reasons for the preservation of specific varieties over great spans of  time. This is probably one of the biggest reasons for the resurgence of  heirlooms in home gardens in the past 10 years, as once people  experience the amazing range and depths of flavors that heirlooms offer,  they are hooked. Taste is once again becoming a viable characteristic  in variety selection for the home garden instead of only production  quantity, uniformity, and disease resistance. 
People are celebrating the fact that taste trumps volume. It’s the  classic quantity vs. quality conundrum, with quality making a comeback.