This famous picture by William Blake of John Bunyan’s character in The Pilgrim’s Progress highlights some key ideas in the mind of a Puritan. He’s on a pilgrimage away from the city of destruction under God’s wrath and headed towards his true home, sin and guilt are heavy on his back, and his eyes are fixed on the Word of God which is leading his path. That’s one quick snapshot of how a Puritan might have understood his spiritual journey. As almost every book and article on Puritanism explains in its first few pages, defining a Puritan or the movement of Puritanism is challenging. It wasn’t a monolithic movement, it spanned more than one hundred years and multiple countries, and the focus varied over time and in different locations. For that reason, most authors are hesitant to actually define Puritanism and instead they’ll offer characteristics.
The English Reformation essentially lasted from 1520-1558 and Puritanism essentially lasted from 1558-1689, although there is much more overlap between the two. An extended timeline on English Puritanism can be found at Christian History. Here are a few lists of characteristics and descriptions of Puritanism. They might not capture everything but they go a long way in conceptually building a framework of Puritanism.
“Puritanism must be understood in two ways: first, as the endeavor to effect thoroughgoing reforms of ecclesiastical practice, and second, as the attempt at a godly life.” 
“Puritansim was essentially a movement for church reform, pastoral renewal and evangelism, and spiritual revival.” 
“A ‘Puritan’ was one who, politically, reacted against the via media of the Elizabethan Settlement in favor of a more thorough reformation in England; who, socially, promoted evangelism, catechism, and spiritual nourishment through the preaching and teaching of the Bible; who, theologically, held the views of Luther’s doctrine of faith (sola fide), Calvin’s doctrine of grace (sola gratia), and the Reformers’ doctrine of Scripture (sola scriptura); and who, devotionally, strove for personal holiness, a practical faith, communion with God, and the glory of God in all things.” 
Characteristics from Worldly Saints by Leland Ryken
1) A religious movement (characterized by a strong moral consciousness)
2) A reform movement (reformation of self, church, and state)
3) A visionary movement (a vision of a reformed society)
4) A protest movement (against Roman Catholicism and at times Anglicanism)
5) A minority movement (minority of population; persecuted minority)
6) A lay movement (the lay Puritan participated in all these characteristics)
7) A biblical movement (the Bible was central to everything)
8) A political and economic movement (politics and religion were intertwined)
7 Characteristics from The Devoted life by Kapic & Gleason
1) A movement of spirituality.
2) Stressed experiencing communion with God.
3) The Bible was the sole authority and supreme source for truth and guidance in life.
4) Augustinian in their emphasis upon human sinfulness and divine grace.
5) Emphasized the work of the Holy Spirit in the believer’s life.
6) Troubled by sacramentalism of Catholicism and its remnants in Anglicanism.
7) At least partially a revival (reform) movement.
 Ernest Kevan, The Grace of Law, 305.
 J.I. Packer, A Quest for Godliness, 28.
 Brian Cosby, “Towards A Definition of ‘Puritan’ and ‘Puritanism,'” 307.