Seeds come in almost endless varieties so it is difficult to make generalizations. Most will contain several basic components like the seed coat, some food for the new plant, and the embryonic plant itself.
Many plants have ingenious seed designs that assist with the plant's attempt at propagating. For example, one plant may create hundreds or even thousands of seeds. The seeds can have wings or propellers that spread in the wind, water, or hook onto animal fur or human pant legs. Others are eaten by animals and passed to a state where they are ready to germinate.
Ornamental grass seed:
The seed coat needs to eventually give way in order for germination to take place. This can happen in a variety of ways. Whether it be from moisture, bacteria, or acidic juices from an animals digestive system something usually needs to crack the casing. Some seeds are better off soaked or nicked before planting.
Dill is a prolific seed producer:
Seeds for beans and peas benefit from inoculation which is a manner of coating the seed with a bacteria culture. The special blend inoculant improves the germination rates of legumes and assists the plant in fixing nitrogen back into the soil.
Some seeds have a built-in delay or dormancy period. Some seeds need to over-winter with a cold period and will not germinate until going through a temperature range. Other seeds require dry or dark dormancy periods. Dormancy's are broken by a variety of factors including water, light, and leaching of chemicals that inhibit germination.
The all-to-familiar dandelion seed is extremely adept at spreading:
So read the seed package and follow the given instructions and feel comfortable that you have increased your knowledge of what seeds are and how they work! Previously Organic Gardening discussed seed collection and storage: Harvesting garden seeds is easy and fun!
Keep your seeds in a cool, dry place for the next planting season. Please do not forget to leave plenty of seeds for the birds and other animals!
If you still want to delve deeper in the subject of seeds OG suggests you read the Wiki pages regarding seeds.
Happy Gardening! Spring is almost here.