The Japanese language accommodates several levels of politeness through different verb endings and alternative expressions and words. There are three general levels of politeness, which are expressed through different kinds of speech. The levels correspond to colloquial, polite, and honorific situations. The honorific level of speech is called keigo.
When speaking to those of much higher social status, (for example, to customers, teachers or elders), you are supposed to use the honorific, keigo speech. Generally, keigo involves using very humble expressions to refer to yourself, and very honorific ones to refer to the person being addressed.
Those studying Japanese as a second language may find keigo complicates their attempts to communicate. However, even native Japanese speakers need considerable exercise in order to be able to correctly express themselves in this formal, honorific way.