Old Norwegian names are confusing, as you'll see in the text below, and working with them requires either recording every variation and letting readability and understanding suffer, or standardising and losing information from the sources. It took me a while to decide on a single way to do it. For some people I've recorded all, or most spellings and name variations. For others I've standardised the spelling and, for example, not recorded whether a particular source spells Anna as Anna or as Anne or Ane. Sometimes I've recorded many spellings because they're unusually varied, or left them out because they weren't, but I've also left out strange spellings and included small variations. In almost all instances though, there are cites and transcriptions showing what spellings, and combinations of names, the records actually used.
In future recording I'm opting for standardising the names as much as is reasonable, and leaving the evidence for spelling variations in cites and source transcriptions.
Having a family name was unusual in Norway, especially outside towns and cities, until the late 19th century, with some families not settling down to one family name until it became compulsory by law in 1923. Instead they had patronymics and farm names. A patronymic of course is pretty much static, but farm names mostly changed with where a person lived, and few people lived on the same farm all their lives. Also the sources vary on whether a person is named with both patronymic and farm name, or just one of them, and sometimes it's not really clear whether the farm name is actually a name or if it should be considered a statement of where the person lived. Adding to that confusion is the lack of standard spelling both of personal names and names of places, and the use of multiple names for a single place. Confused? Let me make up an example to increase the confusion. Let me introduce you to Olav, who I just made up, and let's see how he might be referred to in records:
In the christening records he's probably just referred to as Olav and we must infer his patronymic based on the name of his father (who might be the only parent listed in the oldest sources.) Let's say his father was called Knut (usually spelled Knud in older records). We might also infer a farm name based on where he was born, a small tenant farm called Haug. Now he won't be in any records with the farm name as a child, instead being refered to as Olav Knutsson, son of Knut Knutsson Haug. And unless he dies as a child he's not likely to be in any records until his confirmation anyway.
So at his confirmation we will easily find him as Olav Knutsson, right? Wrong. Although the priest recording his christening might have spelled it that way he might have been Olaf, or Oluf, or Ola to friends and family, and the priest recording his confirmation might choose whatever spelling he prefers based on the pronounciation used, or just based on his own personal standard for names.
Olav/Olaf/Oluf Knutsson is now a grown man, and he'll get married, have children, be a witness at the christenings of children of friends and relatives, and, hopefully, appear in many other records. His first name might be given in multiple spellings, his patronymic as well, if it's not omitted, and he will appear with or without a farm name. So lets look at his farm name. For simplicity's sake we'll decide his parents never moved from Haug, and that he's still living there as a young man, although he gets his income from working on other farms around the parish. So we'll find him again as Olav Knutsson Haug, or possibly Olav Haug, right? Wrong! You see, Haug is a tenant farm and is part of a main farm called Berg. Because of this it's sometimes referred to as Bergeie, literally "property of Berg". If we're lucky we find Olav Haug, but, depending on the priest, we might have to find some other clue to figure out if Olav Bergeie is our Olav, or one of the Olavs living on other tenant farms belonging to Berg. And then Olav starts working as a servant and goes to live with his employers. Now he might be referred to with his "birth farm name" or by his farm name of residence. And his new home is called Øvre Voll, but might be referred to without the "Øvre" (which means upper), which means you could confuse it with Nedre Voll (lower Voll), and Voll might be spelled Woll and...
I hope this might make the varying names on this page a little less confusing, and that it'll help you forgive me for not yet having the perfect system for keeping track of everyone's names.