A ton of changes rework character creation in the Dungeons & Dragons 2024 Player's Handbook. Some of those changes affect your character's Background. Backgrounds tell the story of how a character got here today, at 1st level, a fresh-faced newbie in a world ripe for adventure.
A character's Background is made up of four elements:
Proficiencies – Giving a boost to two skills, e.g., Dexterity (Acrobatics) or Wisdom (Survival). Additionally, you're given a proficiency in the use of one or more tools, e.g., a gaming set or thieves' tools.
Languages – Some backgrounds give you additional languages beyond any you learned from your species (race).
Equipment – A package deal on equipment that makes sense for your selected background, such as an Acolyte background giving you a holy symbol and some incense, or a Hermit background equipping you with a winter blanket and common clothes. (If anything, the meagre equipment packages can serve as a catalyst for seeking the life of an adventurer.)
Suggested Characteristics – These speak to your personality traits, ideals, bonds, and flaws. These are things that largely took over the discussion of Alignment in D&D (Lawful Good, Chaotic Evil, etc.)
For a more comprehensive look at what's changing in D&D 2024, a D&D Beyond post maps it out. Generally, there used to be 13 backgrounds in D&D 5e (2014). But D&D 2024 has 16 backgrounds, some of which were pulled from other 5e sourcebooks, and some are reworked original backgrounds. Here are a few highlights:
In vanilla 5e, abilities (Strength, Dexterity, Constitution, etc.) used to get a three-point boost because of your species. Like a +2 to Dexterity and a +1 to Charisma. But in D&D 2024, those ability boosts come from your background, not your species.
Any and all Feats used to wait until 4th level in vanilla 5e. Now, Origin Feats are added to all backgrounds – which you choose at 1st level; thus, feats are now a 1st level thing.
But hey, if you're a human, that's one way to get an additional feat at 1st level.