Till the date I used to believe that in ruby && and (and) are completely replaceable but in actual its not the case at all.
Precedence of the operators is point to note/remember here.
&& has a higher precedence over = and (and). while (and) has a lower precedence over = and &&.
a = true and false #(Here a = true will be evaluated first and and the value of a becomes true.) a = true && false #(Here true && false will be evaluated first and the value of a becomes false.)