  For a prime $p$ and a commutative ring $R$ with unity, let $W(R)$ denote the
ring of $p$-typical Witt vectors. The ring $W(R)$ is endowed with a
Verschiebung operator $W(R)\xrightarrow{V}W(R)$ and a Teichm\"{u}ller map
$R\xrightarrow{\langle \ \rangle}W(R)$. One of the properties satisfied by $V,
\langle \ \rangle$ is that the map $R \to W(R)$ given by $x\mapsto V\langle
x^p\rangle - p\langle x \rangle$ is an additive map. In this paper we show that
for $p\neq 2$, this property essentially characterises the functor $W$. Unlike
other characterisations, this only uses the group structure on $W(R)$ and hence
is suitable for generalising to the non-commutative setup. We give a
conjectural characterisation of Hesselholt's functor of $p$-typical Witt
vectors using a universal property for $p\neq 2$. Moreover we provide evidence
for this conjecture.
