French tablature was the most common style of tablature used by English and French lutenists and four-course guitarists during the SCA period. Dowland, Morley, Le Roy, etc. all used French tablature in their compositions. The tablature lines are arranged such that:
French tablature uses letters, as opposed to numbers, to represent the frets of the instrument.
For example, the letter “b” above the uppermost line of the tablature indicates that the performer should play the first fret of the first string/course (the note “F” as played on a modern guitar). Note values were often halved for printing in French tablature.
Example of French tablature: First measures of "Come Again" from John Dowland's First Book of Songs (1597)
Keep in mind that these "note values" do not necessarily indicate note duration. Rather, the tablature simply shows the performer the timing between one note and the next. It is up to the performer to interpret how long to hold a note. A general rule of thumb is to hold the note as long as possible, until the tablature later requires that another note (on the same string) takes its place. There are frequent instances, in my opinion, where this rule of thumb should be ignored. Sometimes, holding a note as long as possible results in dissonance where dissonance is clearly not intended by the composer. This is a drawback to the tablature system, but it does make interpreting the period compositions more interesting (at least, I think it does!). Since the tablature system does not depict exactly how long a note should be held, it is up to the performer to interpret the music. A best practice is to hold an individual note as long as possible, unless the music gives a good reason to not do so.
An example of French Tablature, from Gregoire Braising (1553). Compare the French Tablature (uppermost line) to the transcribed staff notation and modern guitar tablature.