What is the significance of version byte and address checksum in version 1 Bitcoin address Pay to public key hash is used in version 1 bitcoin address. Bitcoin address is calculated by sha-256 -ing the public key followed by ripemd160- ing the result. The result can then be encoded in base 58 after 3 more steps as shown in https://en.bitcoin.it/wiki/Technical_background_of_version_1_Bitcoin_addresses 
Version byte and address checksum are added to the ripemd which yeilds same result without them-

This: 
010966776006953D5567439E5E39F86A0D273BEE

And this:
00010966776006953D5567439E5E39F86A0D273BEED61967F6

Yeilds same result when encoded, then
Why is that done?
How could they give the same result? You do RIPEMD160(SHA256(pubkey)). Then you add zero byte 0x0 to this and perform double SHA256. You take the first four bytes and use them as s checksum which means they are control digits which help the wallet determine you didn't misstype the address.

Now you take this whole thing zero-byte+RIPEMD160(SHA256(pubkey))+checksum and you convert it to base58check. Note: zero byte will make the address always start with '1'.

When sender gets a bitcoin address, their wallet converts it from base58check to hex, checks the checksum and removes both the zero-byte and checksum to get RIPEMD160(SHA256(pubkey)). Then it proceeds with scriptPubKey verification.

That's why it is called Pay-to-public-key-hash. Bitcoin address is just a way of encoding a public key hash.