I love cooking but have no academic knowledge of it - can someone explain what is the difference (if any!) between 'gravy' and 'sauce' ?
Easy
Gravy is a naturally thickened reduction of a combination of natural juices resulting from the cooking of meat - usually roasted meats. The combination of juices is infused throughout the entire cooking period during the cooking process, and though it can be thickened by using flour or other meals, using various vegetables is the traditional chef's method of thickening the gravy and maintaining a healthy, wonderful flavour.
Sauces is a more general term and though it can include (although I believe incorrectly) gravy, it is best to think of sauce as purposefully made to have a particular flavour. There are various types of sauces - ranging from pasta sauces to topping sauces to creams to bastings and marinades, etc etc. The base component determines the type of sauce, while the flavouring determines the name - thus a cheese sauce can be cream or milk white-sauce based but the flavouring is cheese. Sauces are not necessarily cooked, and often use other sauces as a base. Mayonnaise for example.
Making your own sauces is extremely easy, and if you perfect a few key sauces you will put an edge on your cooking that will make your guests keep coming back for more.
Try this: instead of buying a bottle of all gold, try my Tomato Sauce recipe...
You'll need:
10 whole peeled tomatoes - jam tomatoes are best for flavour and they make good, thick tomatoe sauces with minimal reduction
Brown Sugar - 1 tbsp spoon
Salt
Pepper (coarsely ground black pepper)
3 or 4 small chillies - I prefer jalapeños, seeds removed, sliced once longitudinally
1 tbsp cider vinegar
1 tsp Worcestershire sauce
1 Leek
Fresh Basil
Chop the tomatoes as finely as you can
Slice the leek finely
Chop the chillies very fine
Chop the basil coarsely
Heat a large saucepan (medium heat) and put a spot of olive oil in the pan, remove from heat, then add the tomatoes, salt and pepper and stir briskly making sure it doesn't stick to the pan. Stir the sugar into the mixture. Put the heat low and replace the pan. Keep stirring, once the tomatoes start to form more liquid in the bottom of the sauce pan, add the leek, place a lid on the pan and allow to simmer for a few minutes. Remove from heat and immediately add the basil - do not stir the mixture immediately - you don't want the basil to burn to the bottom of the pan (basil burns easily), wait a minute or two then pour the sauce into a sieve. Using a spoon or ladel, push the sauce through the sieve catching the juice in the sauce pan, just don't push through too hard, you want the sauce to be solids free (you can keep the left over pulp for baked Mexican foods)

Place the pan back on to low heat, and allow to simmer until thickened. Remove from heat and allow to cool (either in a water bath or covered for 30 - 40 minutes). Place the chillies into a glass bottle, and once the sauce is cooled, stir in the Worcestershire sauce and pour into the glass bottle over the chillies. Replace the lid, place in the refrigerator and leave for 3 days before using for the first time. Use up within 1 week
For a nice spicy sauce, use ground fresh chillies and some dried whole cumin in a spice bag throughout the simmering of the sauce. Remove the spice bag just before pouring into the bottle.
Edit: Sorry about that, connection went loopy.