Through examples... 1. If in a conference hall you happen to meet 50 people and out those 50, 30 shares their email address with u, those 30 are ur leads... 2. If u r tasked with distributing a pamphlet where u wish to tell others about ur newly opened gym.....if u hand over those pamphlets to, let's say 100 people and out that 100, 12 contact u and enquire about ur gym...those 12 are ur leads 3. Let's say if u have posted an advertisement on any of the social networking site...FB, Insta, twitter....and 7 people have posted some positive comments about ur posted advertisement......those 7 guys are ur leads, which later can be converted into potential customers.... ofcourse, not all 7 will be ur customers....some might deny buying ur product..... bottomline:- finding leads is the first step in marketing. These leads are then put through an extensive and rigorous funneling process and finally handful of them are converted into a potential customers....