及（およ）び is a word that functions as a conjunction meaning ‘and’ or ‘as well as’, but is originally the conjunctive form of 及（およ）ぶ, an う-Verb meaning ‘to reach (A)’, or ‘to extend to (A)’. Although it is frequently translated simply as ‘and’, 及（およ）び is a grammar pattern that more literally reflects the meaning of the base verb ‘to extend to (A)’.
Being a conjunction, 及（およ）び will primarily appear at the beginning of a second clause of a sentence, or directly following a noun that something else is ‘in addition to’.

• 免許書（めんきょしょう）及（およ）び印鑑（いんかん）を持（も）ってきてください。
  Please bring your driver's license and seal.
• 学校（がっこう）説明会（せつめいかい）に参加（さんか）されたい方（かた）、及（およ）び体験（たいけん）入学（にゅうがく）をされたい方（かた）は8時（じ）から5時（じ）の間（あいだ）にこちらの電話番号（でんわばんごう）までお電話（でんわ）をください。
  If you would like to participate in a school information session and enroll in a trial lesson, please call this number between 8:00 a.m. and 5:00 p.m.
• 夕食（ゆうしょく）及（およ）び朝食（ちょうしょく）は別料金（べつりょうきん）になります。
  Dinner and breakfast are charged separately.
• 帽子（ぼうし）及（およ）びメガネは外（はず）してください。
  Hats and glasses must be removed.

As 及（およ）び is considered a formal structure, it will primarily appear in documents, articles, and notifications.

• 当店（とうてん）の定休日（ていきゅうび）は月曜日（げつようび）及（およ）び水曜日（すいようび）となっています。
  We are closed on Mondays extending to Wednesdays.