First of all, phishing and spoofing are similar forms of attacks, but not the same. What is the difference between phishing and spoofing emails?
Phishing is a type of social engineering technique that attempts to acquire sensitive information such as passwords, credit cards, social security numbers, etc. Phishing poses as a trustworthy person, so when you get the email it seems like its coming from someone you know. Phishing attacks can be started with a spoofing email. An example of phishing is getting an email from American Express asking you to reset your password, the email may come from what it seems a valid email address, but if look closely, there may be some misspelled words, once you click on the link it takes you a website that looks like American Express but is not, you enter your username and password, and the attackers gain access to your bank account.