A letter of recommendation praises the person being recommended through a written letter. Aspects discussed in a letter of recommendation include qualities of the individual, their characteristics, and capabilities in performing a specific task or function. The most common recommendation letter is addressed to an employer or to an educational institution. In addition, letters of recommendation are frequently written towards scholarship eligibility.
The first sentence of a letter of recommendation should say "To Whom It May Concern", because it is not known exactly who will be reading it and there may be multiple different people reading the letter of recommendation.
In the first paragraph, mention the name of the person being recommended and how long you have known the person. Also mention the capacity in which you are writing the letter of recommendation, what your credentials are or how long you have been working your career.
Write several paragraphs mentioning your experiences with working with the person being recommended, and be sure to include specific examples for more authenticity and to make it more personal. With your descriptions of the experiences you have with the person being recommended, be sure to bring out the qualities of the person.
The final closing of the letter of recommendation should contain the actual recommendation, with wording such as "I wholeheartedly recommend..." naming the person and what you are recommending them for. Reinforce your recommendation by including a short summary of traits of the person being recommended and your continued belief in the person.