Well, some key differences between editions.
Fifth edition aims to keep numbers under control and to be less reliant in the letter of the rules.
Important changes:
- There is a single progression for attacks, saves and skills, if you are proficient with a weapon, spell, skill or saving throw you add this bonus.
- There is a saving throw for each ability score
- All main spellcasters share the same spell progression and can cast freely from spells prepared. Some classes cannot prepare spells only know a limited number of them
- Feats are optional, You can swap a feat for an ability score improvement. These are determined by class level.
- Paladin is a "half caster", they cast spells from second level onwards. They spend spell slots to smite.
This are the basic Rules
http://media.wizards.com/2016/...yerBasicRulesV03.pdf
This is the SRD which has all the classes and only one subclass per class.
http://media.wizards.com/2016/...DND/SRD-OGL_V5.1.pdf
If after reading this, you want to play your paladin in 5e I could use one in my game.(Warning Mature))
link to another game