Ambient pressure concept of pressure becomes irrelevant, and it is undefined at a gravitational singularity. The SI unit of pressure is the pascal (Pa), which is a very small unit relative to atmospheric pressure on Earth, so kilopascals (kPa) are more commonly used in this context. The ambient atmospheric pressure at sea level is not constant: it varies with the weather, but averages around 100 kPa. In fields such as meteorology and underwater diving, it is common to see ambient pressure expressed in bar or millibar. One bar is 100 kPa or approximately ambient pressure at sea level. Ambient pressure may in
Turbo Pascal supported remote debugging via an RS232 communication cable. Over the years, Borland enhanced not only the IDE, but also extended the programming language. A development system based on ISO standard Pascal requires implementation-specific extensions for the development of real-world applications on the platforms they target. Standard Pascal is designed to be platform-independent, so prescribes no low-level access to hardware- or operating system-dependent facilities. Standard Pascal also does not prescribe how a large program should be split into separate compilation units. From version 4, Turbo Pascal adopted the concept of "units" from UCSD Pascal. Units were used as external function libraries,