Here's defining the various categories of visa depending on your purpose of visit.
Single Entry Visa : A single entry visa is valid for only one visit to the destination country. Whatever the purpose of your visit, you shall be eligible for just one entry through the validity of your visa. For instance your visa validity date has not expired but you have already visited the country once, you shall still not qualify for another trip to the said country.
Multiple Entry Visa : This entitles you to multiple visits to the country through your visa's validity tenure. This means you can re-enter the country several times without applying for a fresh visa as long as your within the validity tenure of your visa. Multiple entry visas are largely preferred by businessmen for they can never be certain of the number of visits it might take to close a business deal.
Tourist Visa : This kind of visa is allocated to tourists alone when the purpose of your visit is travelling only and not engaging in any form of commerce. When you plan on a holiday to a foreign location solo or with your family, you will be applying for a tourist visa. It is still easier to get such visas. Other than the requisite documents, you need to provide a proof of your hotel stays and return flight tickets aside from showing a certain specified amount in your bank account to ensure to the local authorities that you will be in charge of yourself during your visit to their country.
Residence Visa : While a residence visa doesn't give you the permit to take up employment in a given country, it entitles you to stay for an extended period of time in a particular country. A residence permit or a residence visa is given to a foreign national to stay for an extended though definite period of time. In many cases, a person may have family residing in a foreign country and by applying for a residence visa you can stay with them for a prolonged duration, several months on end. Of course, it does not entitle you to seek any sort of employment in the foreign country in the interim.
Work Visa : A work permit visa entitles you to take up residence as well as employment for a definite period in a given foreign country. You could either be hired for a specific period of time from 6 months to 1 year, depending on your contract, to perform a job in a foreign country offering you the subsequent right to take up residence in the interim. But in case your stay is prolonged, you need to apply for renewal of your work permit visa. Several Indian companies have tie-ups abroad with their counterparts, and you could be send to accomplish a task to the said foreign country for a specific period of time under a work permit visa.
Student Visa : A student visa is issued to students enrolled at qualified educational institutes world wide. These are non-immigrant visa that does not require its holder to acquire citizenship. Any student with the prospect of attaining higher education in a foreign country needs to get a student visa from that country. Though most countries issue student visa to foreign students to let them attend school within their territory, students still need to primarily enroll at a post-secondary institute for higher learning. So, for instance, you need to go to the United States to study, you would require a student visa as well as a non-immigrant visa for temporary stay or an immigrant visa for permanent residence.
Transit Visa : For those people who wish to transit through Australia shall not qualify for a transit without a transit visa. You need a transit visa even if you fly out of the same airport in which you arrived and on the same aircraft. You need a transit visa even if you remain in the transit lounge and do not leave the airport. A transit visa in case of Australia allows you a maximum stay of 72 hours. A transit visa is very different from a 3-day visitor visa. A transit visa establishes the principal purpose of visit of the applicant before transiting to another country through theirs. The support documents needed to get a transit visa comprise an income proof, employment proof, evidence of travel outside the said country, among other related documents.