Linux - nslookup

How can we look up the MX record for a given domain? How can we determine the mail server for a given domain?

nslookup -type=MX gmail.com

or use http://www.mxtoolbox.com

How can we look up the text record of a given domain?

nslookup -type=txt yahoo.com

How can we lookup a domain using a specific DNS server?

nslookup -type=txt astoundlearning.com dns1.registrar-servers.com

In the above example, we look up the astoundlearning.com domain using the DNS server dns1.registrar-servers.com. Instead of using dns1.registrar-servers.com, we can also use it's IP address.