Formula Logical Implication

For Formulas ${\mathcal{F}}_1,{\mathcal{F}}_2$ ${\mathcal{F}}_1\text{ LIMP }{\mathcal{F}}_2={\mathcal{F}}_1⟹{\mathcal{F}}_2$ means every Truth Assignment in ${\mathcal{F}}_1$ is Satisfied in ${\mathcal{F}}_2$