Remote, hybrid, and onsite
Also called work model, RTO, return to office.
The three work models employers post, distinguished by how many days you're required in an office and from where you're allowed to work.
The labels are used loosely and the details are where the surprises live. "Remote" frequently means remote within a specific country or set of states, for tax and employment-law reasons rather than preference. "Hybrid" ranges from one day a month to four days a week. "Flexible" often means the policy hasn't been decided or is about to change.
Ask three questions before an offer stage: how many days, which days, and how far the acceptable radius is. A hybrid role with fixed anchor days is a different life from one with any-two-days flexibility, and a "remote" role that requires quarterly travel to a hub is a different cost depending on where you live.
Policy volatility is itself a factor to weigh. A number of employers have tightened requirements after hiring people under looser terms, and what's written in a contract is more durable than what's in a posting. If remote work is load-bearing for you, get it into the offer letter.
Job posting
The employer's public description of a role — part specification, part marketing, and rarely a literal list of requirements.
Offer letter
The written document stating the terms of employment — and the only version of the offer that binds anyone.