This talk presents a unified framework for $\delta$-type algebras, obtained by generalizing classical derivations to $\delta$-derivations satisfying the identity $D(x \cdot y)=\delta\bigl(D(x)\cdot y+x\cdot D(y)\bigr).$ We introduce $\delta$-Leibniz algebras, $\delta$-Novikov algebras, (transposed) $\delta$-Poisson algebras, and $\delta$-Novikov--Poisson algebras, and discuss the relationships among these structures. We examine both the similarities and the differences between classical algebras and their $\delta$-type counterparts. In particular, we present examples of finite-dimensional complex simple algebras of $\delta$-type for which no analogous simple objects exist in the classical setting. We also show that the commutator algebra of a $\delta$-Novikov--Poisson algebra naturally gives rise to a transposed $(\delta+1)$-Poisson algebra.