Right—and those “few situations” are actually really important to understand, because they’re the main exceptions to the warrant requirement. Here are some of the most common ones, in plain English:

1. Consent
   If you voluntarily agree to let police search (your car, home, bag, etc.), they usually don’t need a warrant.
   • You generally have the right to say no.
   • If you do say yes, it can be hard to challenge later.
2. Search Incident to a Lawful Arrest
   After lawfully arresting you, officers can search:
   • You and your clothing
   • The area within your immediate reach (for weapons or evidence)
     This is for safety and to prevent destruction of evidence.
3. Exigent (Emergency) Circumstances
   Police can act without a warrant if waiting would create serious risk, like:
   • Someone is in immediate danger
   • Evidence is about to be destroyed
   • A suspect is fleeing or about to escape
4. Automobile Exception
   Because vehicles are mobile and heavily regulated, officers often can search a car with probable cause to believe it contains evidence or contraband, even without a warrant.
5. Plain View
   If an officer is somewhere they’re allowed to be and they can see evidence or contraband in plain view (for example, drugs on a car seat), they can usually seize it and may expand the search based on what they see.
6. Stop-and-Frisk / Pat-Down for Weapons
   If an officer reasonably suspects you’re involved in criminal activity and may be armed, they can briefly stop you and pat down your outer clothing for weapons (a “Terry stop”). It’s supposed to be limited, not a full search.
7. Border and Airport Searches
   At borders and many airport security checkpoints, searches are much broader and generally allowed without a warrant or individualized suspicion.
8. Probatin/Parole Conditions
   If someone is on probation or parole, they may have agreed to reduced privacy rights, including searches by law enforcement or probation officers with less than normal probable cause or even on suspicion alone, depending on the terms and local law.

The details and limits of each exception are very fact-specific and vary by jurisdiction. If a search led to evidence being used against you, a criminal defense attorney can often challenge whether one of these exceptions truly applied—and if not, may be able to argue that the evidence should be suppressed.