• Mechanical Engineering: These engineers design, repair, and install mechanical machines such as engines, refrigerators, and turbines. Mechanical engineers may work in manufacturing and agriculture, as well as in general mechanical design and repair.
• Electrical and Electronics Engineering: Electrical engineers work on electric equipment, such as electric motors and the wiring in buildings. Electronics engineers work on industrial and consumer technologies, like DVD players and telecommunications systems.
• Industrial Engineering: This type of engineering focuses on the machines and methods used in manufacturing and production. Industrial engineers study the way different goods are produced and distributed, in order to streamline the process and make it more efficient. 
• Civil Engineering: Civil engineers design the built environment of everyday life, such as bridges, roads, and dams.
• Aerospace Engineering: Aerospace engineers use principles of mechanical engineering and physics to design planes, satellites, spacecraft and other aircraft.

More than 15 engineering specialties exist; these few are the specialties with the largest number of engineers.

• Associate Degree: 2 years to complete
• Bachelor's Degree: 4 years to complete
• Master's Degree: 2-3 years to complete
• Doctoral Degree: 4-5 years to complete

A two-year associate degree in engineering prepares graduates for a career as an engineering technician. Engineering technicians are more focused on applied aspects of engineering, and they may assist engineers in design, production, and repair. Associate degrees in engineering are offered by community colleges and technical schools. Most staff-level engineering jobs require graduates to have a bachelor's degree in engineering from a school accredited by the Accreditation Board for Engineering and Technology (ABET). In bachelor's programs, students take a curriculum of general education courses, along with math, natural science, and engineering fundamentals classes. Bachelor's programs also require students to take many engineering labs, where they get hands-on experience designing and prototyping machines.

Master's programs in engineering last two to three years, and they allow engineers to study in an even more particular sub-specialization. These graduate degrees may be required for more advanced or supervisory engineering positions. Some engineering master's degrees are coursework-only professional degrees, designed to train engineers in the latest technology in a particular area of engineering. Other master's programs require students to engage in a significant research project, and to write a thesis on their findings. Engineering doctorate programs are designed for students who want to engage in intensive scholarly research in a field of engineering. They require many years of full-time work, and are aimed at individuals who would like to enter an academic career in engineering.

U.S. states require engineers who wish to offer their services directly to the public to be licensed. Exact requirements for licensure vary slightly by state, but all states require engineers to have an ABET accredited undergraduate degree and four years of professional experience as an engineer. In addition, engineers must take and pass the Fundamentals of Engineering exam. Other professional organizations offer voluntary certification in a number of engineering specialties. For example, the American Society of Mechanical Engineers and the American Society of Civil Engineers offer certification to engineers in their respective fields. Voluntary certification can be a way to stay up on the latest techniques and to highlight engineering skills. (BLS)

The types of classes you'll have to take will depend on the type of engineering degree you wish to pursue. There are many types of engineering specializations, with very different focuses. Mechanical, electrical, aeronautical, chemical, and civil engineering are just some of the different types of engineering degrees that are out there. With that said, all engineering degrees require students to have a solid background in math and physics. Since all engineering deals with some sort of physical phenomena, all engineering students need a firm grasp of the tools necessary to interpret these phenomena. Math courses in Ordinary Differential Equations and Linear Algebra are required by most engineering programs, and cover the mathematical techniques that are used to model different types of physical systems.

Physics courses cover equations of motion, light, and electricity, and apply those math skills to the natural world. A first-year physics course in mechanics covers Newton's laws of motion, and how we can quantify and predict movement. A course in light and heat studies lenses, and ways of modeling interference and diffraction in light waves, as well as laws of thermodynamics. Most physics classes also include lab components, where students physically model the systems they are studying in class. Many engineering fundamentals courses also overlap between specific engineering majors. One foundational course called Dynamics has lessons in mechanics that are applicable to everything from small particles to building trusses.

Definitely. Engineering is an incredibly hands-on discipline, which requires students to build models and test their skills in lab courses. Ensure that any online engineering bachelor's degree you're considering has a way for you to get this hands-on experience. Many online programs combine distance learning courses with required on-campus labs.

Several other undergraduate degrees also use engineering principles. The degree in architecture requires students to understand the physical dynamics of the built environment, although it focuses more on building design and less on fundamental engineering principles. A degree in product design utilizes many mechanical engineering principles, and teaches students how to build functional models; product design students also learn art and design principles.

In a computer science degree, students are required to learn math and physics, which they then apply to computer systems and programming. Management science students learn about math, physics, and statistics, and attempt to apply these principles to optimize the efficiency of a business. Degree majors in regular physics and chemistry have many of the same foundational courses involved in mechanical and chemical engineering degrees.