Speed is a beneficial (positive) status effect in Minecraft Java Edition 1.21.
minecraft:speed
Give Speed II for 60 seconds (Java Edition 1.13+; duration in seconds, then amplifier where 0 = level I):
Remove the effect from the nearest player:
Speed increases your walking speed by 20 percent per level and widens your field of view, making it the classic travel and combat-mobility effect.
Brew a Potion of Swiftness from an awkward potion and sugar for three minutes of Speed I, extend it with redstone, or upgrade to Speed II with glowstone dust. Beacons can also grant Speed to everyone in range, and splash and arrow variants exist for sharing it.
Speed II feels dramatic but drains hunger faster through all the extra movement, so pair it with a good food supply. In parkour and PvP, even Speed I changes which jumps and dodges are possible, and it stacks with sprinting and sprint-jumping for the fastest on-foot travel.
The effect ID for Speed is minecraft:speed. Java Edition 1.13+ /effect commands use this namespaced form. On Java 1.12.2 and earlier the numerical ID was 1.
Run /effect give @p minecraft:speed 60 1 to get Speed II for 60 seconds. The first number is the duration in seconds; the second is the amplifier (0 = level I, 1 = level II). Remove it with /effect clear @p minecraft:speed.
Speed is a beneficial (positive) status effect in Minecraft Java Edition, based on its registry category (beneficial).
Drink a Potion of Swiftness, brewed from an awkward potion with sugar. Glowstone upgrades it to Speed II, redstone extends the duration, and a beacon set to Speed grants it continuously in range.
Each Speed level adds 20 percent to walking speed, so Speed I is 1.2x and Speed II is 1.4x normal speed. The boost applies while sprinting too, which compounds the difference.