A security alarm is a system designed to detect intrusions, such as unauthorized entry, into a building or other areas, such as a home or school. Security alarms protect against burglary (theft) or property damage, as well as against intruders. Examples include personal systems, neighborhood security alerts, car alarms, and prison alarms.
Some alarm systems serve a single purpose of burglary protection; combination systems provide fire and intrusion protection. Intrusion-alarm systems are combined with closed-circuit television surveillance (CCTV) systems to record intruders' activities and interface to access control systems for electrically locked doors. There are many types of security systems. Homeowners typically have small, self-contained noisemakers. These devices can also be complicated, multirole systems with computer monitoring and control. It may even include a two-way voice which allows communication between the panel and monitoring station.
St Albans (/sənt ˈɔːlbənz/) is a cathedral city in Hertfordshire, England and the main urban area in the City and District of St Albans. It lies east of Hemel Hempstead and west of Hatfield, about 20 miles (32 km) north-north-west of central London, 8 miles (13 km) south-west of Welwyn Garden City and 11 miles (18 km) south-south-east of Luton. St Albans was the first major town on the old Roman road of Watling Street for travellers heading north and it became the Roman city of Verulamium. It is within the London commuter belt and the Greater London Built-up Area. With a population of 82,146, it is the fourth-most-populous settlement in Hertfordshire.