Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of the words: "Happy Thoughts" surrounded by flowers. The back contains a handwritten note, as well as the stock signature: "From your friends at West Allegheny Middle School" on a sticker.

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a turtle with floral and geometric motifs on its back, legs, and neck. The back contains a handwritten note, as well as a sticker with the stock signature: "From your friends at West Allegheny Middle School."

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a turtle with floral and geometric motifs. The back contains a handwritten note, as well as the stock signature: "From your friends at West Allegheny Middle School."

Post-it note with handwritten message in green marker. The message reads: "May your memories be forever a blessing and may the Holy One hold in his Heart forever."

Note from a member of The Church at Severn Run in Severn, Maryland. The note is enclosed in an envelope with church letterhead, reading: "The Church at Severn Run: Love Well, Live Jesus, Believe Big!" The note inside contains message of condolence and a wish for peace, articulated through citations to the Book of Psalms. The church's contact information is included on the back of the envelope.

Card from a congregant at the Holy Angels Parish. The front cover contains a stock illustration of seven children holding hands around a table with a large goblet and loaf of braided bread, and seven doves. The illustration is labeled: "We are people of God's peace." The inside reads: "The Tree of Life Members, even though you are going through something tough you will get through it by praying and being with each other. Sincerely, Holy Angels CCD."

Square card with white and yellow text against blue background. Card reads, "Mitzvah4Pittsburgh. Some spread darkness. We spread light. Choose a good deed. Choose a Mitzvah. Add light to the world," followed by four options and a place for respondents to list their name and email address. Some names and email addresses have been redacted for privacy.

Program from the November 4, 2018 Sunday worship at Blessed Sacrament Cathedral in Greensburg, Pa. The program contains a special prayer, titled "A Prayer for our Neighbors," which offers words of support for all the victims of the October 27 attack. Signed by two parishioners, Ed and Camille [last name redacted] on the center left.

Post-it note with handwritten message in blue marker. The message reads: "May your memory be for a blessing. Sending love and healing from Jews in Berkeley, CA." Signed with a Star of David.

Summary: Pittsburgh City Paper breaking news report on the October 27 attack. Includes real-time tweets from City Paper publisher Justin Matase and comments from various local elected officials.

Post-it note with handwritten message in black marker. The message reads: "What happened here will not be forgotten." Signed with a Star of David.

Typed letter from a student at Hebrew Academy, a private Jewish day school in Montreal, Quebec. The letter reads: "Dear Rabbi, My name is Joelle. I'm 10 years old. I live in Montreal. I go to Hebrew Academy, a private school. I'm sorry to hear that there was a shooting. I feel so bad. It doesn't matter what religion you are, you have to respect other[s] just the same way you have to respect Hashem (God). We should always know that we are stronger than hate. So bad things can't happen we have to faith and emunah (trust) in Hashem. I feel so bad. From: Joelle. P.S.

Floral tag from floral arrangement sent by Bham. Handwritten note in black ink on printed tag with various flowers in the upper and lower left corners. The reverse is stamped with the contact information for Squirrel Hill Flower Shop.

Handwritten card in colored pencil on paper. The card features a large tree resting on grass in the lower center and reads: "We're thinking of you Tree of Life." It is signed: "[Lov]e Shayna and West Orange, NJ."

Post-it note with handwritten message in blue ink. The message reads: "Prayers for Pittsburg[h]. May this never happen again anywhere." Color bleeding due to exposure to the elements.

Wooden pedestal painted white with white Star of David and red heart affixed to front. Handwritten in pencil and black marker on the Star of David is the name "Sylvan Simon." Collaged onto the heart are white pieces of paper and a translation of Psalm 34:18: "The Lord is close to the broken hearted and saves those who are crushed in spirit." Accompanying image shows all 11 Stars of David in the series.

Envelope addressed to Rabbi Jeffrey Myers of Tree of Life. Front cover of the enclosed Hallmark card features floral imagery and says "Thinking of You." Inside reads: "My only connection to each of you is that of a fellow caring, loving human spirit that has the incredible gift of being able to learn and exist with all other living beings on this Earth. Even though that is my only tie to each of you, it is strong enough to share in your sadness and loss..." Continues on the back: "As a community and as a fellow human. May love always conquer hat and fear.

Floral tag from floral arrangement sent by the Manitoba Islamic Association in Canada. The tag reads: "Words cannot begin to express our sorrow at the senseless attack at a house of worship. Please accept our deepest condolences from the Manitoba Islamic Association." The message is printed on a tag from a local florist.

Handwritten note in pencil on paper. The note, written in bubble letters, reads: "Stronger Than Hate." Illustrated with the adapted Steelers emblem with two diamonds and a Star of David. Creasing and fading due to exposure to the elements at the Wilkins memorial.

Handwritten letter written in black ink on glossy, lined notebook paper. The author, who identifies themself as a Hindu, articulates their belief in the Hindu concept of the soul's eternal nature. They conclude their letter with a Hindu prayer transliterated and translated into English. Fading and spotting due to exposure to the elements at the Wilkins memorial.