Credit score models (algorithms) are a product. Like all products, the consumers (that is, banks and other credit granters) want variety. They each have selected one (or a few) different models that they've decided best suit their needs. Several companies (namely FICO, but also lots of smaller companies) have created their own models that they all tout as being the best.
It goes something like this...
FICO: "Our FICO5 model will qualify more people for your loans, with less risk of defaults!"
Vantage: "No, our VantageScore 2.0 is the best for that!"
FICO: "Oh ya, well we just made FICO8 now, and it's even better!"
Vantage: "Ya, well now we have version 3.0 now, that's even better than FICO8!"
FICO: "Ladies and gentlemen, we present to you FICO9!"
Every model has slight (or in some cases, major) differences in the way they calculate a score from your credit data. That's why everyone's scores are always all over the place. It's a mess.
Luckily for us, we know that FICO is by far the most commonly used by lenders, and we know which versions of FICO are used the most for different types of credit. FICO 8 Bankcard is used the most for credit cards. FICO 8 Auto is used the most for car loans. Etc, etc.
Meanwhile, Vantage is mostly used for credit monitoring websites, and not much else.
Total Loan Balance: $43k / $65k
Total SL: $78k