What is the difference between the several packages that nginx uses openssl?

When compiling nginx today, we found that there are several different packages on openssl: 44412016-Jan-2814: 38: 54openssl-1.0.1r.tar.gz (SHA256) (PGPsign) (SHA1) 51352016-Jan-2814: 38: 54openssl-1.0.2f.tar.gz (SHA256) (P... when compiling nginx today, we found that there are several different packages on openssl:

4441 2016-Jan-28 14:38:54 openssl-1.0.1r.tar.gz (SHA256) (PGP sign) (SHA1)
5135 2016-Jan-28 14:38:54 openssl-1.0.2f.tar.gz (SHA256) (PGP sign) (SHA1)
4906 2016-Feb-15 18:56:05 openssl-1.1.0-pre3.tar.gz (SHA256) (PGP sign) (SHA1)
1420 2016-Feb-13 20:13:39 openssl-fips-2.0.12.tar.gz (SHA256) (PGP sign) (SHA1)
1399 2016-Feb-13 20:13:39 openssl-fips-ecp-2.0.12.tar.gz (SHA256) (PGP sign) (SHA1)

Q:
What is the difference between 1.0 and 2.0?
What is the difference between fips-2.0.12 and fips-ecp-2.0.12?

Which of the following is better for the latest ngnix 1.9?

Reply content:

When compiling nginx today, we found that there are several different packages on openssl:

4441 2016-Jan-28 14:38:54 openssl-1.0.1r.tar.gz (SHA256) (PGP sign) (SHA1)
5135 2016-Jan-28 14:38:54 openssl-1.0.2f.tar.gz (SHA256) (PGP sign) (SHA1)
4906 2016-Feb-15 18:56:05 openssl-1.1.0-pre3.tar.gz (SHA256) (PGP sign) (SHA1)
1420 2016-Feb-13 20:13:39 openssl-fips-2.0.12.tar.gz (SHA256) (PGP sign) (SHA1)
1399 2016-Feb-13 20:13:39 openssl-fips-ecp-2.0.12.tar.gz (SHA256) (PGP sign) (SHA1)

Q:
What is the difference between 1.0 and 2.0?
What is the difference between fips-2.0.12 and fips-ecp-2.0.12?

Which of the following is better for the latest ngnix 1.9?