If you're traveling internationally, many countries have strict requirements regarding the expiration date of passports. Many times, you might not be allowed to enter a country if your passport expires within a certain number of months of your intended departure date.
This expiration window varies between countries, but it's usually around 6 months. For instance, countries within the European Union generally require that passports are valid for at least 3 months beyond the intended date of departure. So if your passport expires in July, and your trip is scheduled for May, you might not be allowed to enter the country!
So avoid having a bad trip, and check your expiration date before your travel date and renew your passport if necessary!