Hi,ENGINEERZ

There are four distinct steps to commercial production of a recording. Recording, editing, mixing, and mastering. Typically, each is performed by a sound engineer who specializes only in that part of production.

Studio engineer could be either a sound engineer working in a studio together with a producer, or a producing sound engineer working in a studio.
Recording engineer is a person who records sound.
Mixing engineer is a person who creates mixes of multi-track recordings. It is not uncommon for a commercial record to be recorded at one studio and later mixed by different engineers in other studios.
Mastering engineer Typically the person who mixes the final stereo tracks (or sometimes just a few tracks or stems) that the mix engineer produces. The mastering engineer makes any final adjustments to the overall sound of the record in the final step before commercial duplication. Mastering engineers use principles of equalization and compression to affect the coloration of the sound.
Game audio designer engineer is a person who deals with sound aspects of game development.
Live sound engineer is a person dealing with live sound reinforcement. This usually includes planning and installation of speakers, cabling and equipment and mixing sound during the show. This may or may not include running the foldback sound.
Foldback or monitor engineer is a person running foldback sound during a live event. The term "foldback" is outdated and refers to the practice of folding back audio signals from the FOH (Front of House) mixing console to the stage in order for musicians to hear themselves while performing. Monitor engineers usually have a separate audio system from the FOH engineer and manipulate audio signals independently from what the audience hears, in order to satisfy the requirements of each performer on stage. In-ear systems, digital and analog mixing consoles, and a variety of speaker enclosures are typically used by monitor engineers. In addition most monitor engineers must be familiar with wireless or RF (radio-frequency) equipment and must interface personally with the artist(s) during each performance.
Systems engineer is a person responsible for the design setup of modern PA systems which are often very complex. A systems engineer is usually also referred to as a "crew chief" on tour and is responsible for the performance and day-to-day job requirements of the audio crew as a whole along with the FOH audio system.
Audio post engineer is a person who edits and mixes audio for film and television.