Hybrid vehicles are JUST gas. They use regenerative braking to reclaim energy, and use that power to make the gas engine more efficient. The engine shuts off at stoplights and low speed, etc. You can entirely forget that they are electric. This benefit is mainly for city driving, but also hilly areas. Flat highway cruising not so much- so they are interesting in that city and highway MPG are very similar, or even inverted like the mid 2000's prius- those had 48 city 45 highway!
PHEV's are "plug in hybrid vehicles" - these have a MUCH larger battery, and you plug them into the wall. These have an electric only range, AND a gas range, You can use a PHEV like a normal hybrid, but it takes some more thought, and is LESS efficient due to the extra battery weight. That said, if most driving is electric only, they are far more efficient than normal hybrids due to just how efficient electric driving can be. My car, the Honda Clarity, has a 17 kWh battery pack. This could charge from empty to full in about 14 hours on a normal outlet, which worked for us for a year. We recently upgraded to "level 2 charging" which is just a 220v outlet in the garage. My cheap 16 amp charger charges the car fully in about 4 hours, but you can go up to 32 amps on my car, faster for others. (I chose 16 amps for lower cost, higher electric efficiency, and the slower charge being less stressful on the battery. Interestingly, 220v charging is MORE efficient than the slow 110v, simply due to the 220v charger design needing to not work as hard to step the voltage up all the way for the battery)
- Plug in hybids charge "quick" relative to full EV's due to the small batteries and low electric only range. On road trips, my car is exactly like driving a regular gas car except that I need to press the "hv" button every time I start the engine to maintain a nice large battery buffer. Otherwise it gets down to "empty" (some charge remaining) which is usually OK, but doesn't leave a huge buffer for mountain passes- admittedly a rare occurrence. (it's a 99 horsepower engine in a 4000 lb car... the battery and engine together give 212hp. The battery buffer allows the car to have full power, and the engine keeps running to bring your buffer back to where you started once you are no longer using it all, such as flat cruise) - this car is really designed as a commute only car, but with a bit of thought it is a great road trip car aside from a small gas tank. Plus, some restaurants have free charging when taking a break from the road! - a PHEV is rarely intended to charge at public stations like an EV, they are really designed around home overnight charging.
Full EV's of course will never use gas.