English law is the common law legal system governing England and Wales, comprising criminal law and civil law. 

English law has no formal codification: the essence of English common law is that it is made by judges sitting in courts applying statute, and legal precedent ("stare decisis") from previous cases. A decision of the Supreme Court of the United Kingdom, the highest civil appeal court of the United Kingdom, is binding on every other court. 

Some rulings are derived from legislation; others, known as common law, are based on rulings of previous courts. For example, murder is a common law crime rather than one established by an Act of Parliament. Common law can be amended or repealed by Parliament; murder, for example, now carries a mandatory life sentence rather than the death penalty. 

The first schedule of the Interpretation Act 1978, defines the following terms: "British Islands", "England", and "United Kingdom". The use of the term "British Isles" is virtually obsolete in statutes and, when it does appear, it is taken to be synonymous with "British Islands". For interpretation purposes, England includes a number of specified elements: 

"Great Britain" means England, Wales, Scotland, their adjacent territorial waters and the islands of Orkney and Shetland, the Hebrides and, by virtue of the Island of Rockall Act 1972, Rockall. "United Kingdom" means Great Britain and Northern Ireland and their adjacent territorial waters, but not the Isle of Man, nor the Channel Islands, whose independent status was discussed in "Rover International Ltd. v Canon Film Sales Ltd." (1987) 1 WLR 1597 and "Chloride Industrial Batteries Ltd. v F. & W. Freight Ltd." (1989) 1 WLR 823. "British Islands"but not "British Isles"means the United Kingdom, the Isle of Man and the Channel Islands.
Does English law have a formal codification?
Who makes it?
What is stare decisis?
Where does it come from?
Where else are ruling derived from?
What is the Supreme Court of the United Kingdom?
What act was passed in 1978
What is the punishment for murder?
What does the Interpretation Act 19787 define?
What does "Great Britain" mean
Are islands a part of that?
Which ones?
What act made Rockall a part of this?
What does United Kingdom mean?
Does that include Isle of Man?
no
 has no formal codification
judges
 it is made by judges sitting in courts applying statute
legal precedent
and legal precedent ("stare decisis")
from previous cases
 ("stare decisis") from previous cases
from legislation
Some rulings are derived from legislation
its highest civil appeal court of the United Kingdom
 Supreme Court of the United Kingdom, the highest civil appeal court of the United Kingdom
the Interpretation Act 1978
 the Interpretation Act 1978, 
a mandatory life sentence
or example, now carries a mandatory life sentence 
it defines the following terms: "British Islands", "England", and "United Kingdom"
 Interpretation Act 1978, defines the following terms: "British Islands", "England", and "United Kingdom"
"Great Britain" means England, Wales, Scotland
"Great Britain" means England, Wales, Scotland,
yes
"Great Britain" means England, Wales, Scotland, their adjacent territorial waters and the islands of Orkney and Shetland, the Hebrides and, by virtue of the Island of Rockall Act 1972, Rockall.
the islands of Orkney and Shetland, the Hebrides and, by virtue of the Island of Rockall
the islands of Orkney and Shetland, the Hebrides and, by virtue of the Island of Rockall
Rockall Act 1972,
by virtue of the Island of Rockall Act 1972,
"United Kingdom" means Great Britain and Northern Ireland and their adjacent territorial waters
"United Kingdom" means Great Britain and Northern Ireland and their adjacent territorial waters
no
 "United Kingdom" means Great Britain and Northern Ireland and their adjacent territorial waters, but not the Isle of Man, 