In my opinion there is a time and a place for both charcoal and briquettes when barbecueing. For me, the principal consideration is what you can easily purchase at a local (or perhaps not so local in our internet shopping era) store. If you can buy barbecue lumpwood charcoal or barbecue briquettes it is useful in some cases to be able to use one over the other.
Some people will say that briquettes are an inferior barbecue fuel to lumpwood. The reasons given are that briquettes are full of filler and other undesireable contaminents. However, I do not really buy that it harmful. After all in our litagous society a barbecue briquette manufacture is hardly going to want to be found to be poisoning it's customers. And, notwithstanding this point, I don't detect a different taste when I barbecue with briquettes.
So don't worry about it too much. If you can only buy briquettes this will do very well indeed. There are some practical benefits too. Barbecue briquettes take up less space for the fuel they contain and will be more suited to foods that need to spend longer on the barbecue or when a longer cooking time is required. That's not to say lumpwood charcoal is not effective under those circumstances but it may require you to refuel.
The main benefit of lumpwood charcoal is that it is faster to light therefore reducing time to cook. So if you are in hurry or time limited in some way lumpwood charcoal let's you barbecue when maybe you would not have considered doing so. If you are planning on cooking some sausages, burgers, steaks or anything else that cooks quickly then lumpwood charcoal will be a good choice too. A chimney starter, if you are using one, will be ready in a matter of minutes and provide more than enough cooking time for these kind of foods.
Charcoal briquettes are possibly more versatile. They take longer to burn down enough to cook over but weight for weight less is required, briquettes will hold their heat longer and whilst perfectly suited to foods that cook quickly will require little or no adjustment to cook foods that require longer to cook such as a roasting joint.
It is important that whichever charcoal you choose that you through away any unburnt charcoal. It won't be any good to use next time. Please do not be tempted to think it will. Charcoal, both lumpwood and briquettes, will absorb moisture from the atmosphere. This will happen more quickly in your barbecue than anywhere else. See Barbecue Care about storing your barbecue. Charcoal's ability to absorb moisture isn't limited to water, it will absorb any other potential contaminent. Don't be tempted, through away the few pennies worth of unburnt charcoal left over and use fresh.
Wood chips and smoke
In my opinion there is no place for liquid smoke in cooking. It is an essence of smoke and there is no reason that with the right techniques you can't impart a beautiful smokey flavour in to your food naturally. So trust me, if you've bought some liquid smoke put it away or better still through it away.
To achieve that wonderful smokey flavour you will need some wood chips or wood chunks. The advantage of a wood chunk rather than chips is that it will tender to smoulder away for longer were as chips can catch fire, smoke and be gone quite quickly. However, it can be difficult to find wood chunks and vice versa so use what you can. Traditional wood flavourings include apple, pecan and paerhaps most well know are mesquite and hickory. There are numerous other woods you can try.
To use the wood chips or chunks you will probably be hot roasting or cooking some Low and Slow bbq. There is a wide spread belief that to prepare the wood for your barbecue that you should soak this in water first. This is competely unfounded. There is no good reason for this. All that happens is that damp wood comes into contact with your hot coals and causes the temperature to drop and stirs ash up. Simply add the wood chips or chunks to the charcoal a handful every 45 minutes to an hour as they come. They will give off a good deal of smoke without detriment to your fire.
The "Smoke Ring" as it is known, is the wonderful pink colour you see on barbecued meat. It will work from the outside in, just like the growth rings on a tree. The lowest, slowest cooked bbq will have a smoke ring that is deep into the meat. If you are cooking brisket the colour may extend all the way through and be difficult to see. In a chicken or on a pork joint though this will be easier to see. The smoke ring shouldn't be confused with the "Bark", a dark finish to your meat that can be almost treacle like in colour after a long cook.