A term in Sᴘᴀʀᴛᴀɴ is a variable, a binding, a reference, an operation or a thunk (i.e. a term that cannot yet be evaluated). For the visualiser, the syntax for a term is as follows:

term ::= <var>
        | bind <var> = <term> in <term> 
        | new <var> = <term> in <term> 
        | ϕ(<term>*;<thunk>*)

thunk ::= <term> | <var>.<term>

where ϕ refers to an operation that has a number of eager arguments (those terms before the ;) and a number of deferred arguments (those thunks after the ;). A thunk is given as either a term, or a term with a bound variable.
Note: We omit the ; when there are no deferred arguments.

Below, we have a list of operations that have been implemented in this visualiser.

Arithmetic Operation	Sᴘᴀʀᴛᴀɴ Operation
n	n
succ n	SUCC(n)
n + m	PLUS(n,m)
n - m	MINUS(n,m)
n * m	TIMES(n,m)

Logical Operation	Sᴘᴀʀᴛᴀɴ Operation
true	TRUE
false	FALSE
a && b	AND(a,b)
a
¬ a	NOT(a)
a == b	EQUALS(a,b)

PCF Operation	Sᴘᴀʀᴛᴀɴ Operation
if b then t else f	IF(b;t,f)
λx.t	LAMBDA(;x.t)
t u	APP(t,u)
rec f.t	REC(;f.t)

Imperative Operation	Sᴘᴀʀᴛᴀɴ Operation
! a	DEREF(a)
a := n	ASSIGN(a,n)
()	UNIT
a ; b	SEC(a;b)

Control Operation	Sᴘᴀʀᴛᴀɴ Operation
callcc(f)	CALLCC(;f)
abort(f)	ABORT(;f)
... break; ...	SCOPE(;w. ... BREAK(w) ...)
... continue; ...	SCOPE(;w. ... CONTINUE(w) ...)