Fighter

Fighters are simply a hoot. They look a little boring at first, but the very wide range of specializations unlock truly powerful melee skills, and the archetypes support individually great artists with blade and bow (Champion), tactical masters (Battle Master), and magical fighters (Eldritch Knight).
The range here is well demonstrated in Nine Princes in Amber, where both Gerard (a massive, close-range brawler) and Benedict (a master tactician and duelist) were Fighters. In more popular media, think of everything from Conan to every character Bruce Willis has ever played to Napoleon.
They lack some of the lore and clear roll-playing hooks, but they are often one of the most important members of a group as they are key to being able to dispatch any foe.
STR is the most important ability for Fighters, unless you want to focus on archery or finesse weapons, in which case it is DEX. CON is next, unless you plan on being an Eldritch Knight, in which case it is INT.

Martial Archetypes

Fighters develop specializations by adopting Martial Archetypes at 3rd Level. You gain features from your Martial Archetype at 3rd, 7th, 10th, 15th, and 18th Level.

The Admiral

This Archetype specializes in leading vessels at sea.

Aerial Knight

This Archetype specializes in airborne combat manouvers.

Arcane Archer

This Archeytpe is true to its name, featuring ranged weapons with magical enhancements.

Arcane Dabbler

This Archetype gains a smattering of arcane abilities to complement their martial skills.

Arcane Knight

This Archetype embeds arcane power into a weapon of their choice (2 variants).

Anointed Warrior

This Archetype employs alchemical enhancements to their martial prowess.

Battle Master

This Archetpye uses special Superiority Dice to enable them to support their allies in battle throug a very wide range of tactics.

Blood Knight

This Archetype uses their own blood to gain advantage in combat. (2 variants, one arcane focused)

Bulette Knight

Often found as Dwarves, this Archetype partners with a burrowing mount.

Brute

This Archetype focuses on direct, immediate combat.

Cavalier

This Archetype specializes at combat while mounted.

Chainmaster

This Archetype focuses on weapons made of chains, posing great danger to others and not a little to themselves (2 variants).

Champion

The most straightforward of the Archetypes, Champions just get better and better at individual combat.

Cinderwood Knight

A battlefield tactics focused Archetype.

Commander

Commanders are able to impact their allies while in the midst of battle.

Duelist

This Archetype focuses on 1-v-1 combat.

Dwarven Defender

Usually found among, yes, Dwarves, this Archetype focuses on providing a firm line of defense for their communities.

Eldritch Knight

This Archetype mixes magical abilities with melee combat, making them more of a hybrid class.

Elemental Blade

This Archetype infuses their weapons with arcane, elemental energies.

Enforcer

This Archetype focuses on tactics and the use of special bloodwork weapons.

Fey Knight

Containing multiple specializations, this Archetype focuses on harnessing the shifting nature of The Feywild.

The Fist

An Archetype focusing on bare-knuckle combat.

Flying Fighter

This Archetype learns to glide and soar in combat.

Forgemaster

This Archetype learns the secrets of smithing their own blades.

Gadgeteer

An Archetype that mixes fighting with Artificer talents.

Gatecrasher

You are first into battle, breaching even arcane wards.

Gladiator

This Archetype focuses on skill in arenas, battle pits, and the like (5 variants).

Glorious Combatant

This Archetype focuses on the skills needed to conquer all with a minimum of damage or impact being suffered in return.

Havoc Runner

Often Gnolls, this Archetype specializes in swift, hit and run tactics.

Holy Knight

Often aligned with angelic entities, this Archetype is devoted to the protection of holy sites and/or the advancement of divine goals.

Holy Trampler

This Archetype embodies the strength of the massive herd beasts.

Immortal

This Archetype is trained to withstand any challenge and persevere.

Iron Bulwark

Usually in service of a deity, this is a defensive focused Archetype.

Janissary

This Archetype focuses on the mastery of a dizzying array of weoponry.

Knight

Chivalry, armor, lances, all that.

Living Weapons

This Archetype has mastered converting their body itself into a weapon.

Masked Warrior

This Archetype--their visage hidden at all times--focuses on mounted abilities.

Mercenary

This Archetype focuses on the versatility and will needed to survive as a sword-for-hire.

Pact Foger

This Archetype focuses on the art of the deal--often with deadly forces.

Phalanx Warrior

This Archetype focuses on mastery of the uses of a shield, as both an offensive and defensive weapon.

Planar Champion

This Archetype focuses on the skills necessary for combat beyond the material plane.

Pugilist

This Archetype are boxers, wrestlers, and pit fighters.

Royal Guard

This Archetype remains alert at all times, coordinating its actions with its allies.

Rune Knight

This Archetype mixes brute strength with the ability to add runic enchantments to weapons and armor.

Samurai

This Archetype focuses on precision and elegance in their melee actions (note that a Paladin subclass may be closer to the Eastern Samurai traditions; also, katanas are cool).

Sharpshooter

This Archetype focuses on ranged weapons.

Siege General

This Archetype specializes in commanding in times of warfare.

Soulknife

This Archetype focuses on a blade made from mental energy.

Squire

This Archetype appears to be a faithful sidekick of another fighter. Appears to be.

Survivor

This Archetype focuses on skills needed to survive in an apocolyptic hellscape.

Sword-Dancer

This Archetype knows that subtlety will always overwhelm pure aggression.

Talon of Horus

This Archetype embodies the power of the hawk, and the deity behind it.

Tunnel Commando

Preferred by Dwarves and Gnomes, this Archetype specializes in battle beneath the surface.

Tunnel Watcher

Often Dwarves, this Archetype specializes in underground defense.

Undying Knight

Fueled by the powers of nature, this Archetype gains regenerative abilities.

Warden

This Archetype focuses on defense and support, especially in the use of a weapon and shield combination.

Some types of fighters are explicitly dark, and or not bound by particular martial etiquette:

Corpse Knight

This Archetype blends fighting with necromancy.

Dark Arts Militant

This Archetype includes the ability to create arcane oils and poisons to coat their weapons.

Dirty Fighter and Wicked Fighter

These Archetypes specialize in the tricks of fighting without regards for the silliness of etiquette.

Available Classes

Artificer

Barbarian

Bard

Cleric

Druid

Fighter

Monk

Paladin

Ranger

Rogue

Sorcerer

Warlock

Wizard

Remember

These are meant as a summary of the class. The official rules should be consulted, either directly or through the DM with any questions or clarifications.
Scroll down for full class details.

Available Races

Dragonborn

Dwarves

Elves

Gnomes

Half-Elves

Half-Orcs

Halflings

Humans

Tiefling

Fighter

Fighters learn the basics of all combat styles. Every fighter can swing an axe, fence with a rapier, wield a longsword or a greatsword, use a bow, and even trap foes in a net with some degree of skill. Likewise, a fighter is adept with shields and every form of armor. Beyond that basic degree of familiarity, each fighter specializes in a certain style of combat. Some concentrate on archery, some on fighting with two weapons at once, and some on augmenting their martial skills with magic. This combination of broad general ability and extensive specialization makes fighters superior combatants on battlefields and in dungeons alike.

hit dice: 1d10

hit points at 1st level: 10 + CON modifier

hit points at higher levels: 1d10 or 6 + CON Modifier

armor proficiencies: All Armor; Shields

weapon proficiencies: Simple Weapons; Martial Weapons

tools:

saving throws: STR; CON

skills: 2 from Acrobatics, Animal Handling, Athletics, History, Insight, Intimidation, Perception, and Survival.

starting equipment:
Chain mail or leather armor; longbow and 20 arrows; a martial weapon and shield or 2 martial weapons; a light crossbow and 20 bolts or 2 handaxes; a dungeoneer's pack or an explorer's pack.

spellcasting:
For the Eldritch Knight, which is a Martial Archetype that combines skills of a Fighter with those of a Wizard.
INT is your spellcasting ability.
Spell Save DC = 8 + Proficiency Bonus + INT modifier
Spell Attack Modifier = Proficiency Bonus + INT modifier

Cantrips

At 3rd Level, you know 2 cantrips from the wizard spell list. You learn an additional cantrip at Level 10.

Spell Slots

The Fighter Table below details how many spell slots you have available. Most of your spells mut be from abjuration or evocation schools. Specifically, 1 of the spells you gain at 3rd Level and the spells you learn at 8th, 14th, and 20th Level can be from any school of magic.

class features:

Fighting Style

At 1st Level, you adopt 1 of 11 fighting styles: Archery; Defense; Dueling; Great Weapon Fighting; Protection; Two-Weapon Fighting, Blind Fighting, Interception; Superior Technique; Thrown Weapon Fighting; or Unarmed Fighting. See PHB 72 and TGE 41-42 for details on each.

Second Wind

At 1st Level, you may use a bonus action to regain HP = 1d10 + your Fighter Level. You regain this after a short or long rest.

Action Surge

At 2nd Level, you can take an additional action. You regain this ability after a short or long rest. At 17th Level, you can use it twice, but only once per turn.

Martial Versatility

At 4th Level, whenever you reach a level that grants the Ability Score Improvement, you may also replace a fighting style or, if you know a maneuver, you may repalce it.

Extra Attack

At 5th Level, you gain an attack whenever you take an attack action. At 11th and 20th Level, you gain additional attacks, giving you 4 at Level 20.

Indomitable

At 9th Level, you can reroll a saving throw if you fail. You regain this ability after a long rest. At 13th Level, you can do this twice between long rests; at 17th Level, you can do this thrice.

subclass options:
FIghters specialize through Martial Archetypes.

LEVEL	PROFICIENCY	FEATURE	SPELL SLOTS GAINED (Eldritch Knight only)
1	+2	Fighting Style Second Wind
2	+2	Action Surge (one use)
3	+2	Martial Archetype	2 1st Level
4	+2	Ability Score Improvement with Martial Versatility	1 1st Level
5	+3	Extra Attack
6	+3	Ability Score Improvement with Martial Versatility
7	+3	Martial Archetype Feature	1 1st Level 2 2nd Level
8	+3	Ability Score Improvement with Martial Versatility
9	+4	Indomitable (one use)
10	+4	Martial Archetype Feature	1 2nd Level
11	+4	Extra Attack (2)
12	+4	Ability Score Improvement with Martial Versatility
13	+5	Indomitable (2 uses)	2 3rd Level
14	+5	Ability Score Improvement with Martial Versatility
15	+5	Martial Archetype Feature
16	+5	Ability Score Improvement with Martial Versatility	1 3rd Level
17	+6	Action Surge (2 uses) Indomitable (3 uses)
18	+6	Martial Archetype Feature
19	+6	Ability Score Improvement	1 4th Level
20	+6	Extra Attack (3)