If you’re reading this with ease, English may be your first language. Yet for billions of people — from Karachi to Quito — the language of Shakespeare can be a colossal struggle. Non-native English speakers may find it tough to order a coffee in English, let alone take an exam or close a business deal. But with these challenges, come opportunities. If you’re passionate about education, languages, or culture — or just inspiring others — a job as an English as a Second Language (ESL) teacher might be a good fit for you.

ESL teachers break down concepts, help to grow their students’ linguistic abilities, and ultimately simplify a frustrating and complex language for non-native speakers. Their work can be hugely rewarding — from teaching people how to thrive in daily life, conduct business, and consume the byproducts of culture.

What’s more, ESL is booming. As of 2015, there were nearly 5 million English language learners in U.S. public schools, notes one Pew Research Center article. And with the U.S. foreign-born population reaching a record 44.4 million in 2017, according to another Pew Research article, it’s likely the number of English Language Learners or ELLs, has steadily grown over the years.

Empathy, enthusiasm, and patience are just a few tools that can help educators excel at the work they do. But becoming an ESL teacher online requires more than soft skills. Those who want to pursue a career in this field must complete specific professional training. Many initially study teaching, linguistics, or English, before completing an online Master of Arts in Teaching English as a Second Language. Knowledge of a second language can help, too.

A quick Google search reveals that the internet is overflowing with online ESL master’s programs, each with its own acronym. Between ESL and TESL, TEFL and TOEFL, all that vocabulary can be confusing. Here’s a breakdown of what they all mean:

• ESL: English as a Second Language
  • Teaching in countries where English is a main or national language, such as the U.S. or India.

• EFL: English as a Foreign Language
  • Teaching in countries where English isn’t widely spoken.

• TESL: Teaching English as a Second Language
  • Teaching courses designed for non-native speakers in countries where English is a main language.

• TEFL: Teaching English as a Foreign Language
  • Teaching courses designed for speakers in countries where English isn’t a main language.

• TOEFL: Test Of English as a Foreign Language
  • Teaching English requires a strong grasp of the language. This is a globally accepted test of English fluency.

TESOL programs fuse the benefits of TESL and TEFL offerings. Rather than focusing on either second- or foreign-language students, it prepares you to instruct and work with both. What does that mean? If you become a TESOL teacher, you can give lessons here in the U.S., or set off on an adventure abroad.

Thanks to the vast range of online TESOL master’s programs to choose from, it is possible to earn a degree that sets you up to become an ESL teacher, without stepping foot in a classroom. Offered by a range of colleges and universities across the country, these specialized programs are designed for remote learners. Channel your enthusiasm into an effective program that may allow you to keep your job and fulfill other personal commitments while you study.

Remote study is an increasingly typical experience within modern education. Online TESOL programs open up the door for you to study from any location, design a flexible course schedule, attend live online classes or rewatch classes, and even engage in part-time study, with minimal disruption to your life.

Prerequisites for master’s in TESOL programs vary by institution, but most require applicants to have a bachelor’s degree and minimum cumulative GPA of around 3.0. In some cases, what you study as an undergraduate is up to you. However, having a background in English, linguistics, or education might ease the transition.

Here’s a general list of other materials your desired school might ask you to submit:

Some programs require applicants to complete a written test, measuring cognitive and logic skills. Applicants whose first language is not English usually have to demonstrate their fluency via the TOEFL.

While the courses online master’s in TESOL students take are typically the same as those offered on campus, curriculum can vary from school to school.

Before applying to a course, you should carefully examine what they offer. There is a key difference between a TESOL certificate and a full master’s degree.

• TESOL Certificate
  • Sometimes costing a couple hundred dollars, certificates far cheaper than full master’s — but they’re also less comprehensive. Lasting several months at most, certificate programs only cover the practical basics of teaching English, rather than delving into theoretical linguistics and pedagogy.

• TESOL Master’s
  • A full Master’s in TESOL is far more wide-ranging than a certificate. In addition to focusing on the practicalities of teaching English — including how to teach grammar and how to run a classroom — they also cover sociolinguistics and other theoretical topics. This sophistication is reflected by length. For full-time students, the course typically takes about two years.

• TESOL Credential
  • To teach at a public school in a given state, you first have to earn state-specific credentials. The specifics vary by jurisdiction but are normally (at least partially) transferable. If you plan to teach ESL, you should make sure that your chosen master’s program allows you to fulfill credentialing requirements. Because they’re aimed at people who want to teach in public schools, credentialed courses often include fieldwork.

From studying how languages are acquired and structured, to absorbing instructional approaches and the importance of social sensitivity in education—an online master’s degree in TESOL should prepare you for life in the classroom. Here are more details of what’s covered:

• Applied Linguistics for English Language Educators
  • Study the grammar and syntax of English, as well as how it’s taught. Learn to compare your English with that of your students and understand what learning methods work for them.

• Theories of Language Learning and Teaching
  • Understand the theories that underpin second-language learning. That includes behavioral, developmental, cognitive and social cognitive theories, and how they all work in practice.

• Assessment and Instruction for Diverse Language Learners
  • Learn how best to test your students in reading, writing, speaking, and listening. Explore how technology can help assess students, and the challenges of setting tests that are free of bias.

• Social Foundations of Language Education
  • Understand why people learn English and the ideal environment for them to do so. Learn about different types of students, and what they need to thrive.

• Approaches and Strategies for Language Teaching
  • Use videos to observe different teaching methods in action, then design and teach your own lesson.

• Technology-Enhanced Language Instruction Design and Practice
  • Make the most of the online teaching revolution. Build on what you’ve learned so far and specialize in remote education, partnering with a class of English learners.

• Teaching Practice to Support Language Learners
  • Focus on curriculum development and lesson planning, creating an environment perfect for learning. Deliver tight, well-organized lessons to a room full of students, and manage class dynamics so that everyone can contribute.

Your TESOL teacher salary often depends on your education, level of experience and seniority, and the type of teaching job you secure. As of 2018, the median annual salary for elementary teachers in the U.S., with the exception of those in special education, is $58,230, according to the Bureau of Labor Statistics (BLS). Half of all high school teachers earned more than $60,320 in 2018. If you work at a school, you can also supplement your income by teaching during vacations.

If you’re well-versed in languages other than English, you can also supplement your income by working as an interpreter or translator in a school or other educational or professional setting. Just make sure that you fulfill the requirements for the position you are considering.

The highest 10% of interpreters and translators earned more than $90,610 in 2018, according to the BLS.

Though the Bureau of Labor Statistics (BLS) doesn’t provide employment projections specifically for ESL teachers, it does estimate a 3% increase in elementary school jobs and a 4% increase in high school teacher jobs by 2028. Employment of teachers will depend largely on state and local government budgets.

Working in a school or in bilingual education is often regarded as the most obvious career path for an ESL expert, but there are plenty of other options too. With more and more foreign companies establishing offices in America, for example, there’s a growing need for quality ESL teachers in business. Working with refugees via NGOs is another option, as is teaching independently—either by meeting students in person or by taking to the internet.

ESL experts also have the option to relocate — some school districts in California even offer a signing bonus for ESL teachers willing to work in its public schools.

From the practicalities of running a classroom— planning lessons and grading assessments — to inspiring your students to improve their vocabulary, the life of an ESL teacher can be rewarding. No two days are the same, and you get to see your successes firsthand: in the growth and improvements of your students.