In the US, there are two types of "PIC" that can be logged & may be interesting to report -- such as for an interview,perhaps perhaps.
Most common when starting out is "sole manipulator of the controls" -- and FAR Part 61 (61.51.e.1.i) defines this. This includes essentially "sole manipulator of the autopilot," so the pilot who is designated as the PF -- pilot flying -- can log his time as PF as PIC, even though the autopilot is engaged & is driving the controls. Early on, the time that you've spent "flying the plane" is of interest -- are you proficient and experienced taking off, landing, using the automation, and so forth. (The standards for logging don't really give a way to distinguish between 10 minutes of hand-flying and an hour on autopilot, vs the whole time being hand-flown. It's not a perfect system.)
Of more interest when interviewing for jobs requiring significantly more experience is PIC as defined in FAR part 1 (1.1, definition of "Pilot in Command"), which amounts to essentially "who signed for the aircraft & is reponsible for the overall flight?" Airlines who are considering hiring you are interested in this sort of PIC time, because they want to know that somebody has entrusted you with their expensive aircraft for enough hours (typically 1000+) that you've proven to be a good pilot IN COMMAND of not just the controls but the overall flight.
One person I talked to who did airline interviews (as an interviewer), said that when he looked at a logbook and saw every other leg logged as PIC, he knew that this pilot was essentially the copilot, the second-in-command of the flight, flying every other leg, but still responsible to the other pilot, who'd signed for the aircraft & was going to answer for it if things went wrong. Then at the point when the logbook started showing every leg as PIC, that's when this pilot became the designated PIC, per the FAR Part 1 definition, and every leg was his responsibility, regardless of who was PF and who was PM. That's the point at which the hours were "interesting" for hiring purposes.
At some point in one's career, the ability to manipulate the controls starts to become a given, and what distinguishes the pilots you want to hire from those you don't becomes factors like judgement or decision making. Regardless of who is flying the leg, somebody has to be the final authority on decisions like, do we need to upload more gas? Is this airport acceptable (not just legal, but wise) as an alternate? How long are we willing to hold before we punt on Plan A and divert to the alternate? All sorts of stuff like that. And the captain is the final authority on all of that just as much on the First Officer's legs flying as he is on his own legs flying. (Which isn't to say he doesn't solicit input -- he certainly should -- but the final decision is his.) Those are the decisions that occur during FAR Part 1 PIC, that may or may not be yours to make during Part 61 PIC. Thus the different ways to count and report one's flight time.
Related discussion of Part 1 and Part 61 PIC time and logging thereof.