Cofiber of spectra
= Cofiber of spectra
{title2=$\operatorname{cofib}(u)$}
= Cofibers of spectra
{synonym}
The homotopy <cofiber of spectra> of $u:A\to B$ is the derived pushout $B\cup_A CA$. It fits into a <cofiber sequence of spectra>.
= Cofiber of spectra
{title2=$\operatorname{cofib}(u)$}
= Cofibers of spectra
{synonym}
The homotopy <cofiber of spectra> of $u:A\to B$ is the derived pushout $B\cup_A CA$. It fits into a <cofiber sequence of spectra>.