What roles of WIF(Wallet Import Format)? I am reading "Mastering Bitcoin" written by Andreas and I found this explanation about "WIF(Wallet Import Format)"


  Key Formats
  
  Both private and public keys can be represented in a number of
  different formats. These representations all encode the same number,
  even though they look different. These formats are primarily used to
  make it easy for people to read and transcribe keys without
  introducing errors.
  
  http://chimera.labs.oreilly.com/books/1234000001802/ch04.html#base58


I have two questions:


I agree with that a private key as decimal numbers is not easy to use for people. However, the hex format and WIF are very similar. I think that WIF has two advantages compared to hex. One is starting with 5 and the next one is having checksum. Are there any good points of WIF.
Can I sign on a transaction by using WIF without the private key?


I'm keen to know about inside bitcoin. Any information will be helpful for me.

Thanks,
Are there any good points of WIF


It is shorter than decimal/hex representation. And, yes, there is checksum.


  Can I sign on a transaction by using WIF without the private key?


WIF is a representation of private key.