Show usage difference between before and let helper of RSpec

diff_before_and_let_spec.rb

# Using before method
before do
  @customer = Customer.new(:name => "Amazon")  
end  
  
it "should be valid" { @customer.should be_valid }  
  
# Using let method  
let(:customer) { Customer.new(:name => "Amazon") }   
  
it "should be valid" { customer.should be_valid }