What are the visa & residency requirements in Sweden?

"In order to visit Sweden, foreign nationals must apply for a visa from the Swedish Embassy or Consulate in their home country. The visa application process requires applicants to provide proof of identity, a valid passport, and other documents such as a letter of invitation, proof of financial means, and proof of accommodation. In order to apply for residency in Sweden, foreign nationals must first obtain a residence permit. This permit is usually granted for a specific purpose, such as work, study, or family reunification. The application process requires applicants to provide proof of identity, a valid passport, and other documents such as a letter of invitation, proof of financial means, and proof of accommodation. Applicants must also demonstrate that they have sufficient knowledge of the Swedish language and culture," mentioned another expat when asked about moving to Sweden.