League of Legends has one permanent map that everyone means when they say "League", one permanent alternative, and a rotating slot that has held some of the best modes the game has ever shipped. Knowing which one to open matters more than it sounds, because they teach completely different skills.

Short answer

Summoner's Rift is the real game, in ranked and unranked forms. ARAM is the one-lane mode for short games and champion practice. The rotating slot brings back modes like Arena and URF periodically. Co-op versus AI and the practice tool are where you should learn anything new.

Summoner's Rift

Five versus five, three lanes, one jungle. Everything the game is designed around lives here: lane phase, objectives, vision, and the long mid-game where matches are actually decided.

  • Ranked Solo/Duo — the ladder most players mean by "ranked", queueable alone or with one friend.
  • Ranked Flex — the same map with a separate rating, built for premade groups.
  • Unranked queues — the same game without the ladder. This is where to try a new role, and where the pick/ban rules are relaxed.

See also: League of Legends Items List — the same League question from the other direction.

ARAM

One lane, random champions, no recall to heal, constant fighting. ARAM strips out macro play entirely and leaves nothing but teamfighting, which makes it the fastest way to learn what a champion's abilities actually do under pressure.

It is also the mode most people play when they do not have forty minutes, and its games are genuinely shorter rather than nominally shorter. The trade is that it teaches you almost nothing about wave management, vision or objectives — skills that decide Summoner's Rift games.

See also: League of Legends Book — the closest League answer to this one.

The rotating slot

Riot cycles limited-time modes rather than running them permanently. The recurring ones:

ModeWhat it is
ArenaSmall-team round-based fights with augments. The most popular returning mode of recent years.
URFMassively reduced cooldowns. Chaotic, very short, and exhausting by design.
One for AllEvery player on a team picks the same champion. A comedy mode that occasionally teaches something real.
Nexus BlitzA compressed map with events. Faster games with Summoner's Rift-shaped decisions.

None of them are permanently available, which is the point — they are events, and they stay fun partly because they leave.

See also: Dota 2 Gameplay — the same question, but for Dota 2.

Where to learn

The practice tool is the most underused feature in the game. It gives you an empty map, free gold, instant levels and a reset button, which is exactly what you need to learn a combo or test whether a specific interaction works. Ten minutes in there beats ten games of guessing.

Co-op versus AI is the second step: the same map, the same objectives, opponents that do not punish a mistake immediately. It is the only sensible place to try an unfamiliar role for the first time.

Teamfight Tactics is a separate game

TFT shares a client and an account with League and shares almost nothing else. It is an auto-battler with its own ladder, its own seasons and its own economy. If someone tells you they play League and they mean TFT, they are not being imprecise — the two have diverged completely.

Which to play

  • Learning a champion? Practice tool, then ARAM to see the abilities in fights.
  • Learning a role? Unranked Summoner's Rift. Nothing else teaches lane phase.
  • Twenty minutes free? ARAM or whatever is in the rotating slot.
  • Trying to climb? Ranked Solo/Duo, one or two champions, and no other mode for a while.

League of Legends FAQ

How many game modes does League have?

Two permanent ones — Summoner's Rift and ARAM — plus a rotating slot that hosts several modes across a year.

Is ARAM good for improving?

For teamfighting and champion knowledge, yes. For everything else Summoner's Rift tests, no.

Will URF come back?

It returns periodically. Riot has not made it permanent, and the rotation is announced per patch.

Does ARAM have its own rank?

No. It has no ladder, which is a large part of why people find it relaxing.

Use the practice tool to learn, ARAM to have fun, and Summoner's Rift when you actually want to find out whether you are improving.