SLA vs SLO

An SLA is a formal document or statement that makes a commitment to customers. On the other hand, SLOs are the core content of an SLA that make specific and measurable commitments. SLA is a whole while SLOs are part of SLAs. An SLA contains many SLOs as target for metrics such as uptime and customer satisfaction rate. An SLA is a binding contract that is most legal wordage by content. On the other hand, SLO while also being binding to a certain extent there is no legality to this binding as is the case with SLA.

via: https://www.quora.com/What-is-the-difference-between-SLA-and-SLO