what is the meaning of Charter- party in maritime law and shipping law?

Documents containing all the terms and conditions of the contract between
a shipowner and a charterer. Charter- parties, or charters as they are often
referred to, fall into two main categories: voyage charter- parties and time
charter- parties. Time charters are contracts for the hire of a ship whereas
voyage charters cover the space in a ship.
Most charter- parties are standard forms. Different standard forms have
evolved for different trades. BIMCO (the Baltic and International Maritime
Council) publishes voyage charter- parties for cement, coal, fertilisers, gas,
grain, ore, stone, tankers and wood, as well as a number of general charters. It
also publishes a number of time charters, for use in different situations. There
are also a number of so- called private forms, that is, charter- parties developed
and published by individual companies, both for voyage and time charters.
The majority of these are produced by the major oil companies. An example
is BeePeeVoy 4, a BP voyage charter- party.
Charter- parties contain various clauses setting out the rights and responsibilities
of both parties in relation to such matters as payment of freight or
hire and contingencies for strikes, general average and war. They also contain
details relating to the individual contract, such as the amount of freight, lay
time, demurrage, the ship’s construction, speed and consumption. The older
forms leave spaces for this information, while the newer types – known as
box- layout charters – have boxes into which the specific information is
inserted. For an example of a box- layout charter, see Gencon under Voyage
charter and Figure 16.
The standard clauses may be varied and/or added to by agreement of the
two parties. When a significant number of clauses are added, these may be
included in an addendum to the charter.
Charter- parties are signed by both the shipowner and the charterer or their
agents. When signed by an agent, it is normal to add the words as agent only.