What are the skills to add hops?

Is there any techniques for putting the hops? Putting hops is a must for brewing beer. In the specific beer brewing, according to the order, there are some ways:

1. Former wort hops: Adding hops after the first collection of wort and malt mashing, in this temperature hops in the bitter acid and wort will play a complex chemical reaction, so that the bitter taste of hops More smooth, more refreshing, this method is often used in many traditional German beer and American heavy flavored beer.
2.Bitter flower addingt: Adding hops in the beginning of wort boiling, this time to add the hops can be relatively limited releasr of bitter acid.
3.Body flover adding method:Adding hops 10-30 minutes before wort  boiling finish. this time to add the hops although the bitterness and flavor are not the maximum extration, but it can affect the wine, bring some hops unique Taste.
4.Fragrant flower methodiling:adding hops in the last of wort boiling, this time will not release too much pain, but it can keep the aroma directly to the beer.
5.Dry hops method: Adding hops in the fermentation is basically completed, generally put 5to10days, can geratly enhance the beer floral, IPA beer necessary process.