A survey of the uses of these words in Johannine literature will be conducted.
ἀγάπη (agape): "The quality of warm regard for and interest in another, esteem, affection, regard, love (without limitation to very intimate relationships, and very seldom in general Greek of sexual attraction)."1 This word appears in the noun form 30 times in 25 verses of Johannine literature (John 5:42; 13:35; 15:9,10,13; 17:26; 1 John 2:5,15; 3:1,16,17; 4:7,8,9,10,12,16,17,18; 5:3; 2 John 3,6; 3 John 6; Revelation 2:4,19).2 This word can also refer to "a common meal eaten by early Christians in connection with their worship, for the purpose of fostering and expressing mutual affection and concern, [e.g.] fellowship meal, a love-feast."3 However, it is not used directly in this sense in New Testament literature. The word is consistently translated as "love" in modern English translations of Johannine literature.4 The word also appears as a verb (ἀγαπάω) 72 times in 51 verses in Johannine literature and is translated consistently as "to love." I also want to point out that this word is not reserved for divine, unconditional love as I have once heard erroneously espoused. The term is often used to express human and even sinful affection, such as how men love darkness rather than light (John 3:19).
φιλέω (fileo): "[T]o have a special interest in someone or someth[ing], freq[ently] with focus on close association, have affection for, like, consider someone a friend."5 This word occurs as a verb 15 times in 12 verses in Johannine literature (John 5:20; 11:3,36; 12:25; 15:19; 16:27; 20:2; 21:15,16,17; Revelation 3:19; 22:15). The term does not appear as a noun (φιλία, friendship) in Johannine literature. This word is often associated with "brotherly love" due to a related word that means exactly this (φιλαδελφία, philadelphia), but when ἀδελφός (adelphos, brother) isn't added to the word, it means the "love between friends." This verb is also consistently translated as "to love" in modern English translations.
Here is a Bible word study showing all of the words in the Greek that were translated into English as "love" in the NASB translation6 of Johannine literature and their frequency of occurrence:

The verb φιλοπρωτεύω appears in the above diagram, and it means "to have a special interest in being in the leading position, wish to be first, like to be leader" (cf. 3 John 9).7 It does not inherently mean "to love," but is often translated as "loves to be first," hence its appearance in this chart (which begins with the English word "love" and works backwards to the Greek). Another common word for love, ἔρως (eros, erotic love), is not used in Johannine literature. The word στοργή (storge, familial love) means "affection" in modern Greek and is included in the link you referenced, but it does not appear in Johannine literature. Its only appearance in the New Testament is as a compound word with φιλέω: φιλόστοργος (philostorgos, loving dearly / mutual love) in Romans 12:10.
A textual example where both ἀγαπάω and φιλέω occur in the same context is in John 21:15-17, which has been covered in another question which you referenced. Addressing the use of both verbs in this context as well as in several others, user swasheck writes:
To force ... a distinction between ἀγαπάω and φιλέω is disingenuous.
There are places where this distinction is inappropriate (2 Sam. 13:4
Amnon ἀγαπῶ Tamar, John 5:20 The Father φιλει The Son, 2 Tim. 4:10
Demas αγαπησας the present world, 1 John 2:15 Do not αγαπατε the
world, John 3:19 the men ἠγάπησαν the darkness).
An alternative solution is that in this instance, the author was
attempting to use variety within the text, assigning words to
operators in order to maintain a clear narrative that comes to a
satisfying conclusion.
There appears to be little difference in meaning between the two words.
Sources
1 William Arndt, Frederick W. Danker and Walter Bauer, A Greek-English Lexicon of the New Testament and Other Early Christian Literature, 3rd ed. (Chicago: University of Chicago Press, 2000), 6.
2 I obtained these results (and all other search results in this response) by conducting a morphology search in Logos Bible software (v5) for the lemma in Johannine literature within the 27th edition of the Nestle-Aland Greek New Testament, utilizing Logos Greek Morphology.
3 Arndt, Danker, and Bauer, 7.
4 I compared the NET, NKJV, and ESV translations of these verses (here and for all other English translation comparisons in this response).
5 Arndt, Danker, and Bauer, 1056.
6 I also checked the ESV and NKJV and had similar results.
7 Arndt, Danker, and Bauer, 1058.