The Director is responsible for creative control over of a film and is in charge of the actors and technical staff. The Director works with the Producer to hire the staff and actors for a film and must have a familiarity with all aspects of filmmaking. Directors pick locations for filming, set up the camera angles and organise the script into a shooting schedule for the scenes. On Set the Director must guide the actors to act out the scenes according to the way they planned together. Directors must also work with his cinematographer in order to plan out things like camera angles and lighting for the scenes. The most important thing the director must do is read the script and plan how the scenes will play out. At the end of the day the Director and some of the crew and actors will look at the “rushes” of scenes and decide whether they need to be shot again or printed.
Joss Whedon: Raised in New york and moved to Los Angeles where he got his first TV writing job
“After relocating to Los Angeles, Whedon landed his first TV writing job on “Roseanne”, and moved on to script a season of “Parenthood”. He then developed a film script which went on to become Buffy the Vampire Slayer (1992). Whedon was very unhappy with the final film – his original script was extensively re-written and made lighter in tone. After this he earned screenwriting credits on such high profile productions as Alien: Resurrection (1997) and Toy Story (1995), for which he was Oscar nominated. He also worked as a ‘script doctor’ on various features, notably Speed (1994/I).”
Motion graphics designer:
This is a job that revolves around designing and animating a wide range of graphics in 2d and 3d for film trailers, commercials and viral internet campaigns. In recent years with advancement of technology motion graphics design has become increasingly popular and is opening the doors to creative minds everywhere.
Motion graphics designers are often recruited from graduates of interactive media and artistic graphics design courses. Alan Shisko says “take a look at motion graphics and ask yourself if you CAN do it, not just whether you WANT to do it. Do you ‘live’ in a visual world?”  which implies it is helpful to have some kind of artistic talent to work in this field.
A few final words from Alan Shisko “I like to say that motion graphics is like architecture: so many disciplines wrapped up into one complex package. It’s technical, it’s artistic, it’s easy to “do” but so very hard to do well.” 
Some of the necessary skills for motion graphics design include graphics (moving pictures and illustrations), typography (working with types of fonts, density, spacing and justifying text), working computer skills (particularly graphics software packages), and the ability to use animation, camera techniques and editing software. 
An Executive Producer is responsible for getting the production made. His or her duties will include the hiring of the crew and personnel, overseeing the budget, making key decisions throughout the production, ensuring the overall quality control of productions, and making sure that the final product conforms to the commissioners’ specifications. The Executive producer isn’t normally involved with any of the technical aspects of filmmaking but will handle all the business and legal side of things.
In order to become an executive producer one must possess the following qualities and skills: Good business skills which will involve budget, marketing and production costs. Leadership skills as you have to make a lot of decisions on the spot that could decide the fate of the production. A good executive producer must also have a knack for problem solving as we have no idea what kind of things might emerge that potentially hinder your production.
Co-producers are similar to the Line producer in that they are responsible for logistical and business portions of the film production phase. They are legally responsible for ensuring the health and measures are in place and up to standard. They carry out risk assessments, where the co-producer differs from a line producer is they have more creative input such as assisting the head of the production with casting, finding a director, and recruiting the key heads of department.
“Where the Co-producer is a partner or corporate officer of the production entity producing the film, he or she plays a key role in the development of the film project, assists with the physical production, or supervises post-production to enable the Producer to move on to another production. Where the Co-producer is the lead Producer from another production entity that is producing the film as part of an international co-production, he or she will usually raise a significant portion of the budget for the film, but have less creative input than the lead Producer.” 
Co-producers must have a good knowledge of the various aspects of the film industry and an understanding of the market place to determine things like what is currently popular in the mainstream film industry. They must practical and skilled thinkers.
The Production managers co-ordinate the production and make of decisions that decide the ultimate fate of a project. They are relied upon to be efficient and economical when scheduling the shoots, negotiating deals for the crew, dealing with insurance for the entire production, securing location bookings and hiring technical staff. Production managers work with the producers in pre-production to discuss the scripts and plan a shooting schedule, estimating a budget and managing the production team. In order to become a successful production manager one must be highly motivated, posses a dynamic personality, an understanding of networking, experience with accounting and be able to work under pressure.
The word cinematographer applies to many different jobs that revolve around camera operation and photography. The main goal of cinematographers is to take what is written down in a script and envision it as a moving image then bring it to life with the camera. The cinematographers have creative control over the position of the cameras, the type of cameras used, lenses, filters, and lighting and camera angles. They also have roles in post-production, which includes inspecting the final product to ensure colouring, lighting and camera are, as they desired. They have a responsibility to ensure quality control in the final project.
Editing assistants by definition “work in Post Production Facilities Houses which provide complete end to end services for off-line, on-line and non-linear editing, visual effects, and DVD production to the independent, corporate and broadcast media sectors.”  This implies that they work with the editors to do technical support and many menial jobs like logging and capturing, encoding, and exporting. He/she would usually arrive at work before the editor to prepare the equipment for the day ahead.
Most edit assistants begin their careers as runners who work within the company, most post-production companies don’t normally hire directly from college media courses. Edit assistants normally work for three to four years before becoming fully qualified editors unless they display skill or talent in which they can be promoted in just one year.
In order to become an editing assistant you would need to know your way around editing software, file types, and file codexes. you need to be familiar with on-line, off-line and non-linear forms of editing. you must work within the industry practices when comes to labeling and storage of tapes.
Skillset.com  recommends the following skills:
advanced IT skills;
effective team working skills;
excellent communication skills;
a high level of organisational skills and precise attention to detail;
initiative and problem solving skills;
diplomacy and sensitivity when working with clients;
knowledge of the requirements of the relevant Health and Safety legislation and procedures.
Edit assistant is an entry level position which often translates to a freelance contract, Editing more often than not is freelance except in corporate film making.