Basil is one of the most popular of the culinary herbs.  It is a(well behaved) member of the mint family, and is grown as an annual plant in Missouri.   It requires full sun and well-drained soil.  Basil may even repel some harmful insects that plague tomatoes and peppers, and is often companion-planted with them for this effect.

VARIETIES
There are many varieties of basil, and there is one for every gardener's personal taste and culinary use.   My favorite is the lettuce-leaf basil, a variety called "Mammoth" (pictured above).  Its leaves are huge and puckered, resembling lettuce leaves, which I find easy to pick for use in pesto, or tomato sauce, or for drying.  For gardeners that want something really easy,  Globe Basil grows tiny leaves in a rounded shape, and are easy to use in recipes, since chopping the leaves isn't necessary.  

A very pretty basil is the Purple Ruffles variety.  Its taste is very much the same as the standard basil, but has a lovely dark purple leaf that looks lovely in the garden, as well as on the plate.   One year I grew Cinnamon Basil, which has the same basil scent, with a warm hint of cinnamon.  I loved the smell of this one, and used it the same way I used standard basil.  This variety is attractive, with a burgundy tint to the leaves.  Lemon basil also has a  wonderful fragrance and is good for cooking in certain dishes where you want hints of lemon.

CULTURE
Basil is very easily grown from seed.  I scatter seed over the prepared area directly outdoors after the soil has warmed.  It is important to wait until it stays warm outdoors before planting.  Sprouts should be thinned at least six inches apart (they will branch), but I get greedy and like to crowd mine to three inches.
Foliar-feed occasionally with an organic fertilizer (fish emulsion, seaweed or kelp mixture) several times during the growing season.  Do this early in the morning or late in the afternoon, as the wet leaves will scorch in the sun.   Leaves should be ready for harvest within 4-6 weeks from planting.  When the plant begins to send up flower spikes, cut back to the larger green leaves (about 8-12 inches, depending on variety) and plants will branch and produce more leaves before attempting to flower again.  This can be repeated.  Once the plant goes to flower, leaf production will decrease dramatically, so this trick can extend your harvest. 
Towards the end of it's lifespan, basil will persist in going to seed even though it has branched from pruning.   At this time, I will continue to cut back on half of the planting area, leaving the other half to go to seed for next year's crop.

USES
You name it..I drop a few clean leaves in tomato sauce during the last 15 minutes of cooking, make a pesto (see Recipes), dry the leaves to use whole later, or grind for use in other recipes that call for Italian seasoning. 

You can make Italian dipping oil using basil and other herbs such as rosemary, oregano, fennel, garlic, thyme, and sage.  Clean and dry the herbs, bruise, and add to a clean bottle.  Add extra-virgin olive oil to the herbs, almost to fill the bottle. Shake or swirl oil jar every few days.  Strain herbs from oil by pouring through strainer into another container.  Heat the oil in the microwave until hot (but not boiling) to kill any organisms that may cause spoilage.  Seal with cork or rubber lid and store away from sunlight in a cool place.  Keeps for several months, and can be used in any recipe that calls for olive oil, and for dipping Italian bread.   

You can also make a wonderful flavored vinegar using purple basil and white vinegar.  Place a sprig of purple basil in a clear wine bottle filled with white vinegar.  Place a cork in the bottle and let the mixture steep for two weeks at room temperature.  The vinegar will turn a nice pink, and the flavors will blend into the vinegar.  You can also use other herbs, such as chives, tarragon, and/or nasturtium.