Melee Attack

Used in hand-to-hand combat, a melee melee attack allows you to attack a foe within your Reach. A melee attack typically uses a handheld weapon such as a sword, a Warhammer , or an axe. A typical monster makes a melee attack when it strikes with its claws, horns, teeth, tentacles, or other body part. A few spells also involve making a melee attack.
Most creatures have a 5-foot Reach and can thus attack targets within 5 feet of them when making a melee attack. Certain creatures (typically those larger than Medium) have melee attacks with a greater reach than 5 feet, as noted in their descriptions.
Instead of using a weapon to make a melee weapon attack, you can use an unarmed strike: a punch, kick, head-butt, or similar forceful blow (none of which count as weapons). You can also use an improvised weapon, such as a rock, a mug of ale, or a broken chair leg.
When you make a melee attack, you add your Strength modifier to your attack and damage rolls unless you are wielding a finesse weapon.