A search warrant is a judge’s order that tells the police to search a specific place, like a person’s home or office.
When they do search, the police may have the authority to take specific items from a home or office as evidence. Evidence is the information presented in the case. Sometimes a search warrant can also tell the police to arrest someone.
In some situations the police can search a place without a warrant. This is a complicated issue; if you have any questions speak to an attorney.