Beer kits are the quickest and easiest way to learn the basics and start brewing. The standard and variety of kits has increased greatly in the last 20 years and it is now very easy to brew a good beer from a kit. All beer kits include malt extract and brewers yeast. The malt extract in a beer kit is basically a concentrated wort which has already had the hops added effectively doing the hardwork for you.
Generally kits come in two forms, 1kg kits and 3kg kits. A 1kg kit generally requires you to add extra fermentable ingredients (i.e. sugar or malt extract) to the brew. A 3kg kit doesn't require any extra ingredients, everything is included in the kit. Above you can see an example of 1kg (left) and 3kg (right) kits.
To make these kits you mix the wort in boiling water, add fermentable sugars (if using a 1kg kit), pour the resultant liquid into the fermenting bucket, top it up to 23 litres with cool water, check the temperature to make sure it is between 18-26 degC and mix in the yeast. Leave it in a warm place for 1-2weeks maintaining the temperature at around 18-26degC then bottle or keg. When bottling, approximately 1/2 teaspoon of sugar per 500ml bottle should be added before sealing the lid. When kegging use approximately 85g in the keg before sealing. This is to prime the beer which will give you the gas so that your beer has fizz. Leave for 1 week in a warm place then move to a cooler place to condition and clear. The longer you leave your beer to condition the better it will taste. Try tasting a bottle after 1 week then try again after 4 weeks. You will notice a huge improvement.