Urinary tract infections (UTIs) are a common type of infection that occurs in the urinary system. UTIs can be caused by bacteria or other pathogens, and can lead to symptoms such as frequent urination, pain or discomfort during urination, and a feeling of urgency to urinate. There are also several synonyms for UTIs, including bladder infections, cystitis, pyelonephritis, and urethritis. These terms are used to describe different types of UTIs that may occur in different parts of the urinary system, such as the bladder, kidneys, or urethra. If left untreated, UTIs can lead to serious complications, so it's important to seek medical attention if you suspect you have symptoms of a UTI.