So far, with our advice, the vesion of Minecraft you play has not mattered. Now it does. On Java (the PC/Mac/Linux version), the 1.9 combat update made axes deal the most damage with the most cooldown. Swords are fast, but don't deal as much damage. In pre 1.9 Java, swords can block and attack, sheilds don't exist, axes are weak, and armor gets worse as it loses durability. On Bedrock (the post-2016 console/mobile/alternative PC version), you have sheilds, but swords are strong and weapon cooldowns don't exist.
Popular severs may include Player vs. Player (PvP) combat minigames.