For an in-depth understanding, please refer to the example below:
William wanted to schedule a Lead Call for Now, so William went to the Lead module. William clicked on Lead and selected Edit from the Action title, against Bryans Name.
After, William went to Activities and created a Lead Call for Bryan. However, William wanted to schedule a Lead Call for Now. So, William Selected Now and filled out the required fields.
If William wanted to schedule a Lead Call for Later, he would have selected Later as the option. William knew that the difference between a Now and Later call, is that a Now call is booked for Immediate Action and a Later Call is scheduled for sometime in the future. Whether that is Tomorrow or a Later Date. Plus, if William wanted a Later Call, he would have to input the Start and End Time accordingly.