Outcrossing:
An Outcross breeding is one in which the Sire and Dam do not share any common ancestors in the last 5 generations. Outcrossing may be done to bring together unrelated bloodlines that may compliment each other.
Linebreeding:
Quite often you will see on a pedigree a statement that that particular dog or litter has been linebred on another dog. This basically means that a certain dog shows up in the pedigree on both the sire and dams side, no more than 5 generations back. Linebreeding on a particular dog is a decision that (should be) made before breeding takes place, and is usually done to emphasize or bring out the qualities in the litter of the dog (or dogs) to be linebred on.
How to read and understand linebreeding:
Linebreeding will usually be stated using numbers, and the name of a dog. The numbers represent the generation in the pedigree, and on which side, the dog appears. These numbers will usually appear “# – #” or “#, # – #, #” etc. The first number or numbers tells you in which generation(s) this dog appears on the Sires side of the pedigree; the second set, the Dams side. The Sire and Dams numbers are separated by a dash (-). If there is more than one number on either side, this simply means that the dog appears in more than one spot in the Sire or Dams Pedigree.
For example, “4,5-5” on “Sam” would mean that “Sam” shows up in the 4th AND 5th generation on the Sires side, and in the 5th generation on the Dams side. The reverse is true if the numbers were placed “4-5,5” then “Sam” would show up in the 4th generation on the Sires side and the 5th generation twice, on the Dams side.
Usually, on a pedigree, the linebreeding will be stated as “Linebred #-# on Some Dog”. For example, “linebred 4-5 on Odin Tannenmeise” (a frequent occurrence). What this statement means is that the particular dog or litter has Odin Tannenmeise in the 4th Generation on the Sires side, and the 5th Generation on the Dams side. A good way to practice determining linebreeding is to look at a pedigree for which the linebreeding is know, and see if you can find the dogs in the right generations and vice versa. There are also some websites (such as Schafer.is, if the dog is in the database), which will tell you the linebreeding on a particular dog, or the prospective linebreeding for a particular litter.
Linebreeding can be a very useful tool in a breeding program. By linebreeding on a very genetically influential dog, you can bring out the qualities of that dog generations down the line without heavy inbreeding. However, linebreeding on a particular dog may also bring out the less than desirable qualities in that dog, so it should be done with caution and education. The SV Breeders rules will not allow linebreeding closer than 2-3 or 3-2 (including with siblings of those dogs). Linebred 2-3 is the maximum.
Inbreeding:
While most Linebreeding is also inbreeding, most don’t consider a breeding to be “inbreeding” unless the common ancestor is in the first or second generation, (for example, a Father/Daughter mating). Inbreeding can be very dangerous and is known for bringing out “faults” or other problems (including genetic ones) in a particular bloodline.
Article from http://www.4gsd.net/pedigrees.html